模板

推荐一份大佬写的模板

/*
	2018.12.2
	今天自习课闲来无事,把部分学过的模板了打一遍,集中于此文件,便于未来复习
	2018.12.3
	继续补坑
	2018.12.4
	翘了一节微机课来补坑
	2018.12.5
	update lct
	2018.12.6
	update quickRead
	2018.12.9
	update sort
	2018.12.12
	update 时隔多天, update inv && suffixSort
	2018.12.23
	update string && Möbius
	2019.01.21
	准备期末考试,时隔一个月才来机房,然而期末依然炸了qwq
	update 杜教筛
	2019.02.14
	update CG
	2019.04.03
	update splay FFT graph
        2021.07.08
        修改了部分单词拼写错误,觉得自己两年前就像个sb
*/

/*
	所有代码未经编译,正确性未知,如有错误欢迎指正
	code by Ηydra
*/
#include <algorithm>
#include <cctype>
#include <complex>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <iostream>
#include <string>
#include <vector>
#define min(l, r) ((l) < (r) ? (l) : (r))
#define max(l, r) ((l) < (r) ? (r) : (l))
using std::swap;
namespace init
{
// Not Recommended
// #define getchar() (p1 == p2 && (p2 = (p1 = buf) + fread(buf, 1, 1 << 21, stdin), p1 == p2) ? EOF : *p1++)
// char buf[1 << 21], *p1 = buf, *p2 = buf;
// 需C++11
template <typename T>
void rd(T &s)
{
	bool p = 0;
	char ch;
	s = 0;
	while (ch = getchar(), p |= ch == '-', !isdigit(ch))
		;
	while (s = s * 10 + ch - '0', isdigit(ch = getchar()))
		;
	s *= (p ? -1 : 1);
}
template <typename T, typename... Args>
void rd(T &s, Args &... args)
{
	rd(s);
	rd(args...);
}
// NOIP用
void rd(int &s)
{
	s = 0;
	int p = 0;
	char ch;
	while (ch = getchar(), p |= ch == '-', !isdigit(ch))
		;
	while (s = s * 10 + ch - '0', isdigit(ch = getchar()))
		;
	s *= (p ? -1 : 1);
}
char rdch_int()
{
	char ch;
	while (ch = getchar(), ch < '0' || ch > '9')
		;
	return ch;
}
char rdch_char()
{
	char ch;
	while (ch = getchar(), !isalpha(ch))
		;
	return ch;
}
} // namespace init

namespace segment_tree
{
#define mid(l, r) ((l + r) >> 1)
#define ls(x) ((x) << 1)
#define rs(x) (((x) << 1) | 1)
#define fa(x) ((x) >> 1)
#define len(x) (tree[x].r - tree[x].l + 1)
const int N = 1000000;
struct node
{
	long long l, r, val;
	long long lzy1, lzy2;
} tree[N << 4];
inline void updata(int x)
{
	tree[x].val = (tree[ls(x)].val + tree[rs(x)].val);
}
inline void downdata(int x)
{
	if (tree[x].lzy2 > 1)
	{
		tree[ls(x)].lzy2 *= tree[x].lzy2;
		tree[rs(x)].lzy2 *= tree[x].lzy2;
		tree[ls(x)].lzy1 *= tree[x].lzy2;
		tree[rs(x)].lzy1 *= tree[x].lzy2;
		tree[ls(x)].val *= tree[x].lzy2;
		tree[rs(x)].val *= tree[x].lzy2;
	}
	tree[x].lzy2 = 1;
	if (tree[x].lzy1)
	{
		tree[ls(x)].lzy1 += tree[x].lzy1;
		tree[rs(x)].lzy1 += tree[x].lzy1;
		tree[ls(x)].val += tree[x].lzy1 * len(ls(x));
		tree[rs(x)].val += tree[x].lzy2 * len(rs(x));
	}
	tree[x].lzy1 = 0;
}
void build(int i, int l, int r)
{
	tree[i].l = l;
	tree[i].r = r;
	tree[i].lzy1 = 0;
	tree[i].lzy2 = 1;
	if (l == r)
	{
		init::rd(tree[i].val);
		return;
	}
	int m = mid(l, r);
	build(ls(i), l, m),
		build(rs(i), m + 1, r);
	updata(i);
}
void add(int i, int l, int r, long long k)
{
	if (tree[i].l == l && r == tree[i].r)
	{
		tree[i].val += k * len(i);
		tree[i].lzy1 += k;
		return;
	}
	downdata(i);
	int m = mid(tree[i].l, tree[i].r);
	if (l > m)
		add(rs(i), l, r, k);
	else if (r <= m)
		add(ls(i), l, r, k);
	else
		add(ls(i), l, m, k),
			add(rs(i), m + 1, r, k);
	updata(i);
}
void mul(int i, int l, int r, long long k)
{
	if (tree[i].l == l && r == tree[i].r)
	{
		tree[i].lzy1 *= k;
		tree[i].val *= k;
		tree[i].lzy2 *= k;
		return;
	}
	downdata(i);
	int m = mid(tree[i].l, tree[i].r);
	if (l > m)
		mul(rs(i), l, r, k);
	else if (r <= m)
		mul(ls(i), l, r, k);
	else
		mul(ls(i), l, m, k),
			mul(rs(i), m + 1, r, k);
	updata(i);
}
long long query(int i, int l, int r)
{
	if (tree[i].l == l && tree[i].r == r)
		return tree[i].val;
	downdata(i);
	int m = mid(tree[i].l, tree[i].r);
	if (l > m)
		return query(rs(i), l, r);
	else if (r <= m)
		return query(ls(i), l, r);
	else
		return query(ls(i), l, m) + query(rs(i), m + 1, r);
}
#undef ls
#undef rs
#undef mid
#undef fa
#undef len

} // namespace segment_tree

namespace fenwickTree
{
#define lowbit(x) ((x) & -(x))
const int N = 100000;
int tree[N];
int del1[N], del2[N];
int sum[N];
int tot;
void add(int *d, int x, int k)
{
	while (x <= tot)
		d[x] += k,
			x += lowbit(x);
}
int query(int *d, int x)
{
	int ans = 0;
	while (x)
		ans += d[x],
			x -= lowbit(x);
	return ans;
}
//单点修改 区间查询
void add_point_normal(int x, int k)
{
	add(tree, x, k);
}
int query_interval_normal(int l, int r)
{
	return query(tree, r) - query(tree, l - 1);
}
//区间修改 单点查询
void add_interval_normal(int l, int r, int k)
{
	add(tree, l, k);
	add(tree, r + 1, -k);
}
int query_point_normal(int x)
{
	return query(tree, x);
}
//区间修改 区间查询
void add_interval_special(int l, int r, int k)
{
	add(del1, l, k);
	add(del1, r + 1, -k);
	add(del2, l, k * l);
	add(del2, r + 1, -k * (r + 1));
}
int query_interval_special(int l, int r)
{
	return sum[r] + (r + 1) * query(del1, r) - query(del2, r) - (sum[l - 1] + l * query(del1, l - 1) - query(del2, l - 1));
}
//代替平衡树部分操作
int hs[N]; //大部分情况需将操作数离散化
void del(int x)
{
	--sum[x];
	add(tree, x, 1);
}
void insert(int x)
{
	++sum[x];
	add(tree, x, -1);
}
int find_rank(int x)
{
	int ans = 0, cnt = 0;
	for (int i = 21; i >= 0; --i)
	{
		ans += 1 << i;
		if (ans > tot || cnt + tree[ans] >= x)
			ans -= 1 << i;
		else
			cnt += tree[ans];
	}
	return hs[ans + 1];
}
int my_rank(int x)
{
	int ans = 1;
	--x;
	while (x)
		ans += tree[x],
			x -= lowbit(x);
	return ans;
}
int pre(int x)
{
	insert(x);
	int ans = find_rank(my_rank(x) - 1);
	del(x);
	return ans;
}
int nxt(int x)
{
	insert(x);
	int ans = find_rank(my_rank(x) + sum[x]);
	del(x);
	return ans;
}
#undef lowbit
} // namespace fenwickTree

namespace SPLAY
{
const int MAX = 200000;
int fa[MAX], val[MAX], sze[MAX], cnt[MAX], son[MAX][2];
int rt;
int tot = 0;
int fre[100000];
int top = 0;
int new_node()
{
	return top ? fre[top--] : ++tot;
}
void updata(int x)
{
	sze[x] = sze[son[x][0]] + sze[son[x][1]] + cnt[x];
}
void rotate(int x, int &k)
{
	int y = fa[x], z = fa[y];
	bool p = son[y][1] == x;
	if (y == k)
		k = x;
	else
		son[z][son[z][1] == y] = x;
	fa[x] = z;
	fa[y] = x;
	fa[son[x][p ^ 1]] = y;
	son[y][p] = son[x][p ^ 1];
	son[x][p ^ 1] = y;
	updata(y);
	updata(x);
}
void splay(int x, int &k)
{
	int y, z;
	while (x != k)
	{
		y = fa[x], z = fa[y];
		if (y != k)
		{
			if ((son[z][1] == y) == (son[y][1] == x))
				rotate(y, k);
			else
				rotate(x, k);
		}
		rotate(x, k);
	}
}
void insert(int &o, int x, int f)
{
	if (!o)
	{
		o = new_node();
		val[o] = x;
		cnt[o] = 1;
		sze[o] = 1;
		son[o][0] = son[o][1] = 0;
		fa[o] = f;
		splay(o, rt);
	}
	else if (x == val[o])
	{
		++cnt[o];
		splay(o, rt);
	}
	else
		x < val[o] ? insert(son[o][0], x, o) : insert(son[o][1], x, o);
}
void find(int o, int x)
{
	if (x == val[o])
		splay(o, rt);
	else
		x < val[o] ? find(son[o][0], x) : find(son[o][1], x);
}
void merge(int l, int r)
{
	if (!l || !r)
	{
		rt = l ^ r;
		return;
	}
	int o = l;
	while (son[o][1])
		o = son[o][1];
	splay(o, l);
	rt = l;
	son[l][1] = r;
	fa[r] = l;
	updata(rt);
}
void del(int x)
{
	find(rt, x);
	if (cnt[rt] > 1)
	{
		--cnt[rt];
		--sze[rt];
		return;
	}
	fre[++top] = rt;
	fa[son[rt][0]] = fa[son[rt][1]] = 0;
	merge(son[rt][0], son[rt][1]);
}
int my_rank(int x)
{
	insert(rt, x, 0);
	int ans = sze[son[rt][0]];
	del(x);
	return ans;
}
int find_rank(int o, int x)
{
	return sze[son[o][0]] < x ? sze[son[o][0]] + cnt[o] >= x ? val[o] : find_rank(son[o][1], x - (sze[son[o][0]] + cnt[o])) : find_rank(son[o][0], x);
}
int pre(int x)
{
	int o = rt, ans = -1;
	while (o)
		x > val[o] ? (ans = val[o], o = son[o][1]) : o = son[o][0];
	return ans;
}
int nxt(int x)
{
	int o = rt, ans = -1;
	while (o)
		x >= val[o] ? o = son[o][1] : (ans = val[o], o = son[o][0]);
	return ans;
}
void dfs(int o)
{
	if (!o)
		return;
	dfs(son[o][0]);
	std::cout << val[o] << " ";
	dfs(son[o][1]);
}
} // namespace SPLAY

namespace SPLAY_interval
{

const int MAXN = 5000000;
int fa[MAXN], son[MAXN][2], sze[MAXN], val[MAXN];
int tag1[MAXN], tag2[MAXN];
int sum[MAXN], maxl[MAXN], maxr[MAXN], maxsum[MAXN];
int fre[MAXN], cnt = 0, top = 0;
int rt;
int new_node()
{
	return top ? fre[top--] : ++cnt;
}
#define mid(l, r) (((l) + (r)) >> 1)
#define ls(o) (son[o][0])
#define rs(o) (son[o][1])
void updata(int o)
{
	sum[o] = sum[ls(o)] + sum[rs(o)] + val[o];
	sze[o] = sze[ls(o)] + sze[rs(o)] + 1;
	maxl[o] = max(maxl[ls(o)], sum[ls(o)] + val[o] + maxl[rs(o)]);
	maxr[o] = max(maxr[rs(o)], sum[rs(o)] + val[o] + maxr[ls(o)]);
	maxsum[o] = max(max(maxsum[ls(o)], maxsum[rs(o)]), maxr[ls(o)] + val[o] + maxl[rs(o)]);
}
void push_down(int o)
{
	int v;
	if (tag1[o])
	{
		int c = val[o];
		if ((v = ls(o)))
		{
			tag1[v] = 1;
			tag2[v] = 0;
			val[v] = c;
			sum[v] = c * sze[v];
			maxl[v] = maxr[v] = (c > 0 ? sum[v] : 0);
			maxsum[v] = (c > 0 ? sum[v] : c);
		}
		if ((v = rs(o)))
		{
			tag1[v] = 1;
			tag2[v] = 0;
			val[v] = c;
			sum[v] = c * sze[v];
			maxl[v] = maxr[v] = (c > 0 ? sum[v] : 0);
			maxsum[v] = (c > 0 ? sum[v] : c);
		}
		tag1[o] = 0;
	}
	if (tag2[o])
	{
		if ((v = ls(o)))
		{
			tag2[v] ^= 1;
			swap(ls(v), rs(v));
			swap(maxl[v], maxr[v]);
		}
		if ((v = rs(o)))
		{
			tag2[v] ^= 1;
			swap(ls(v), rs(v));
			swap(maxl[v], maxr[v]);
		}
		tag2[o] = 0;
	}
}
void rotate(int x, int &k)
{
	int y = fa[x], z = fa[y];
	int p = rs(y) == x;
	if (y == k)
		k = x;
	else
		son[z][rs(z) == y] = x;
	fa[x] = z;
	fa[y] = x;
	fa[son[x][p ^ 1]] = y;
	son[y][p] = son[x][p ^ 1];
	son[x][p ^ 1] = y;
	updata(y);
	updata(x);
}
void splay(int x, int &k)
{
	int y, z;
	while (x != k)
	{
		y = fa[x], z = fa[y];
		if (y != k)
			rotate(ls(z) == y ^ ls(y) == x ? x : y, k);
		rotate(x, k);
	}
}
void init(int o)
{
	fa[o] = son[o][0] = son[o][1] = tag1[o] = tag2[o] = sum[o] = maxl[o] = maxr[o] = maxsum[o] = 0;
}
void build(int &o, int l, int r, int *a, int f)
{
	if (l > r)
		return;
	o = new_node();
	int m = mid(l, r);
	init(o);
	fa[o] = f;
	val[o] = a[m];
	sze[o] = r - l + 1;
	if (l == r)
	{
		sum[o] = maxsum[o] = val[o];
		maxl[o] = maxr[o] = max(val[o], 0);
		return;
	}
	build(ls(o), l, m - 1, a, o);
	build(rs(o), m + 1, r, a, o);
	updata(o);
}
int find(int k)
{
	int o = rt;
	while (true)
	{
		push_down(o);
		if (sze[ls(o)] + 1 == k)
			return o;
		if (sze[ls(o)] + 1 > k)
			o = ls(o);
		else
			k -= (sze[ls(o)] + 1), o = rs(o);
	}
}
int split(int pos, int tot)
{
	int l = find(pos), r = find(pos + tot + 1);
	splay(l, rt);
	splay(r, rs(l));
	return ls(r);
}
void insert(int pos, int tot, int *a)
{
	int l = find(pos + 1), r = find(pos + 2);
	splay(l, rt);
	splay(r, rs(l));
	build(ls(r), 1, tot, a, r);
	updata(r);
	updata(l);
}
void dfs_del(int o)
{
	if (!o)
		return;
	fre[++top] = o;
	dfs_del(ls(o));
	dfs_del(rs(o));
}
void del(int pos, int tot)
{
	int o = split(pos, tot);
	dfs_del(o);
	ls(fa[o]) = 0;
	updata(fa[o]);
	updata(rt);
}
void modify(int pos, int tot, int c)
{
	int o = split(pos, tot);
	val[o] = c;
	sum[o] = c * sze[o];
	if (c > 0)
		maxsum[o] = maxl[o] = maxr[o] = sum[o];
	else
		maxsum[o] = c, maxl[o] = maxr[o] = 0;
	tag1[o] = 1;
	tag2[o] = 0;
	updata(fa[o]);
	updata(rt);
}
void reverse(int pos, int tot)
{
	int o = split(pos, tot);
	tag2[o] ^= 1;
	swap(maxl[o], maxr[o]);
	swap(ls(o), rs(o));
	updata(fa[o]);
	updata(rt);
}
int get_sum(int pos, int tot)
{
	int o = split(pos, tot);
	return sum[o];
}
int max_sum()
{
	return maxsum[rt];
}
void main(int *a, int n)
{
	a[1] = a[n + 2] = maxsum[0] = -0x3f3fffff;
	build(rt, 1, n + 2, a, 0);
}
#undef ls
#undef rs
#undef mid
} // namespace SPLAY_interval

namespace lct
{
const int N = 1000000;
int cnt;
int head[N], nxt[N], to[N];
int sze[N], son[N], dep[N], top[N], rk[N], id[N], fa[N], ed[N];
void dfs1(int u)
{
	sze[u] = 1;
	for (int i = head[u]; i; i = nxt[i])
	{
		int v = to[i];
		if (v == fa[i])
			continue;
		dep[v] = dep[u] + 1;
		fa[v] = u;
		dfs1(v);
		sze[u] += sze[v];
		if (sze[v] > sze[son[u]])
			son[u] = v;
	}
}
void dfs2(int u, int t)
{
	top[u] = t;
	id[u] = ++cnt;
	rk[cnt] = u;
	if (son[u])
		dfs2(son[u], t);
	for (int i = head[u]; i; i = nxt[i])
	{
		int v = to[i];
		if (v == fa[u] || v == son[u])
			continue;
		dfs2(v, v);
	}
	ed[u] = cnt;
}
void add1(int x, int y, int k)
{
	while (top[x] != top[y])
	{
		if (dep[top[x]] < dep[top[y]])
			std::swap(x, y);
		fenwickTree::add_interval_special(id[top[x]], id[x], k);
		x = fa[top[x]];
	}
	if (dep[x] < dep[y])
		std::swap(x, y);
	fenwickTree::add_interval_special(id[y], id[x], k);
}
int query1(int x, int y)
{
	int ans = 0;
	while (top[x] != top[y])
	{
		if (dep[top[x]] < dep[top[y]])
			std::swap(x, y);
		ans += fenwickTree::query_interval_special(id[top[x]], id[x]);
		x = fa[top[x]];
	}
	if (dep[x] < dep[y])
		std::swap(x, y);
	ans += fenwickTree::query_interval_special(id[y], id[x]);
	return ans;
}
void add2(int x, int k)
{
	fenwickTree::add_interval_special(id[x], ed[x], k);
}
int query2(int x)
{
	return fenwickTree::query_interval_special(id[x], ed[x]);
}
} // namespace lct

namespace eulerFunction
{
const int N = 10000000;
int vis[N];
int phi[N];
int pri[N], cnt;
long long SolveWithlogN(long long n)
{
	int sum = n;
	for (long long i = 1; i * i <= n; ++i)
		if (n % i == 0)
		{
			sum -= sum / i;
			while (n % i == 0)
				n /= i;
		}
	if (n > 1)
		sum -= sum / n;
	return sum;
}
int main(int n)
{
	vis[1] = 1;
	for (int i = 2; i <= n; ++i)
	{
		if (!vis[i])
			pri[++cnt] = i,
			phi[i] = i - 1;
		for (int j = i * 2; pri[j] * i <= n; ++j)
		{
			vis[pri[j] * i] = 1;
			if (i % pri[j] == 0)
			{
				phi[i * pri[j]] = phi[i] * pri[j];
				break;
			}
			else
				phi[i * pri[j]] = phi[i] * phi[pri[j]];
		}
	}
	return 0;
}
} // namespace eulerFunction

namespace prime
{
void solveWithN(int n)
{
	eulerFunction::main(n);
}
bool solveWithsqrtN(long long n)
{
	if (n == 1)
		return 0;
	for (long long i = 2; i * i <= n; ++i)
		if (n % i == 0)
			return 0;
	return 1;
}
bool solve_develop(int n)
{
	if (n == 1)
		return 0;
	if (n == 2 || n == 3)
		return 1;
	if (n % 6 != 1 && n % 6 != 5)
		return 0;
	for (long long i = 5; i * i <= n; i += 6)
		if (n % i == 0 || n % (i + 2) == 0)
			return 0;
	return 1;
}
} // namespace prime

namespace qpow
{
//please use this when p approaches LONG_LONG_MAX
//warning : this function is very slow(logB)
long long mul(long long a, long long b, long long p)
{
	long long s = 0;
	for (; b; b >>= 1, a = (a + a) % p)
		if (b & 1)
			s = (s + a) % p;
	return s;
}
long long pow_special(long long a, long long b, long long p)
{
	long long s = 1;
	for (; b; b >>= 1, a = mul(a, a, p))
		if (b & 1)
			s = mul(s, a, p);
	return s;
}
long long pow_normal(long long a, long long b, long long p)
{
	long long s = 1;
	for (; b; b >>= 1, a = (a * a % p))
		if (b & 1)
			s = (s * a) % p;
	return s;
}
} // namespace qpow

//haven't finished
namespace exgcd
{
typedef long long ll;
void exgcd(ll a, ll b, ll &x, ll &y, ll &gcd)
{
	if (!b)
		x = 1,
		y = 0,
		gcd = a;
	else
		exgcd(b, a % b, y, x, gcd),
			y -= (a / b) * x;
}
// ax = 1 (mod p)
// (a, p) = 1
ll inv(ll a, ll p)
{
	ll x, y, g;
	exgcd(a, p, x, y, g);
	if (g != 1)
		return -1;
	while (x < 0)
		x += p;
	return x;
}
} // namespace exgcd

namespace inv
{
typedef long long ll;
// p is a prime && (a, p) == 1
ll FermatLittleTheorem(ll a, ll p)
{
	return qpow::pow_special(a, p - 2, p);
	// return qpow::pow_normal(a, p - 2, p);
}
// (a, p) == 1
ll EulerTheorem(ll a, ll p)
{
	return qpow::pow_special(a, eulerFunction::SolveWithlogN(p) - 1, p);
	// return qpow::pow_normal(a, eulerFunction::SolveWithlogN(p) - 1, p);
}
ll exgcd(ll a, ll p)
{
	return exgcd::inv(a, p);
}
void solve_normal(ll n, ll p, ll *ans)
{
	ans[1] = 1;
	for (ll i = 2; i <= n; ++i)
	{
		ans[i] = (-(p / i) * ans[p % i]) % p;
		if (ans[i] < 0)
			ans[i] += p;
	}
}
void solve_fac(ll p, ll *fac, ll *facinv, ll *inv)
{
	facinv[0] = fac[0] = 1;
	for (ll i = 1; i < p; ++i)
		fac[i] = fac[i - 1] * i % p;
	facinv[p - 1] = EulerTheorem(fac[p - 1], p);
	for (ll i = p - 2; i >= 1; --i)
		facinv[i] = facinv[i + 1] * i % p;
	for (ll i = 1; i < p; ++i)
		inv[i] = facinv[i] * fac[i - 1] % p;
}
// O(n + logp) 离线求n个数在模p意义下的乘法逆元
void solve_special(int n, ll *a, ll *s, ll *invs, ll *inv, ll MOD)
{
	s[0] = 1;
	for (int i = 1; i <= n; ++i)
		s[i] = (s[i - 1] * a[i]) % MOD;
	invs[n] = qpow::pow_special(s[n], MOD - 2, MOD);
	for (int i = n - 1; i >= 1; --i)
		invs[i] = invs[i + 1] * a[i + 1] % MOD;
	for (int i = 1; i <= n; ++i)
		inv[i] = invs[i] * s[i - 1] % MOD;
}
} // namespace inv

namespace Möbius
{
const int N = 10000000;
int mu[N] = {0}, vis[N] = {0}, pri[N] = {0}, cnt = 0;
void get_mu(int n)
{
	mu[1] = vis[1] = 1;
	for (int i = 2; i <= n; ++i)
	{
		if (!vis[i])
			pri[++cnt] = i,
			mu[i] = -1;
		for (int j = 1; j <= cnt && pri[j] * i <= n; ++j)
		{
			vis[i * pri[j]] = 1;
			if (i % pri[j] == 0)
				break;
			mu[i * pri[j]] = -mu[i];
		}
	}
}
//f(n) = n / 1 + n / 2 + ... + n / n
int get_sum(int n)
{
	int ans = 0;
	for (int l = 1, r; l <= n; l = r + 1)
	{
		r = (n / (n / l));
		ans += (r - l + 1) * (n / l);
	}
	return ans;
}
} // namespace Möbius

namespace sum
{
typedef long long LL;
const int maxn = 1700000;
int N;
LL s1[maxn + 100], s2[1300];
int vis[1300];
LL S(int n)
{
	if (n <= maxn)
		return s1[n];
	int x = N / n;
	if (vis[x])
		return s2[x];
	vis[x] = 1;
	LL &ans = s2[x];
	ans = (1 + n) * 1ll * n / 2;
	for (int l = 2, r; l <= n; l = r + 1)
	{
		r = (n / (n / l));
		ans -= (r - l + 1) * S(n / l);
	}
	return ans;
}
} // namespace sum

namespace FFT
{
const int MAXN = 500000;
struct comp
{
	double x, y;
	comp(double _x = 0, double _y = 0) : x(_x), y(_y) {}
} A[MAXN], B[MAXN], eps[MAXN], ieps[MAXN];
comp operator+(comp a, comp b)
{
	return comp(a.x + b.x, a.y + b.y);
}
comp operator-(comp a, comp b)
{
	return comp(a.x - b.x, a.y - b.y);
}
comp operator*(comp a, comp b)
{
	return comp(a.x * b.x - a.y * b.y, a.x * b.y + a.y * b.x);
}
const double pi = acos(-1);
void init(int len)
{
	for (int i = 0, l; l = (1 << i), l <= len; ++i)
	{
		eps[i] = comp(cos(2 * pi / l), sin(2 * pi / l));
		ieps[i] = comp(cos(2 * pi / l), -sin(2 * pi / l));
	}
}
void FFT(comp *x, int len, comp *p)
{
	for (int i = 0, j = 0; i < len; ++i)
	{
		if (i > j)
			std::swap(x[i], x[j]);
		for (int l = len >> 1; (j ^= l) < l; l >>= 1)
			;
	}
	for (int i = 1, l; (l = 1 << i) <= len; ++i)
	{
		int mid = l >> 1;
		for (int j = 0; j < len; j += l)
		{
			comp w0(1);
			for (int k = j; k < j + mid; ++k)
			{
				comp t = w0 * x[k + mid];
				x[k + mid] = x[k] - t;
				x[k] = x[k] + t;
				w0 = w0 * p[i];
			}
		}
	}
}
int main()
{
	int n, m;
	init::rd(n, m);
	for (int i = 0; i <= n; ++i)
		init::rd(A[i].x);
	for (int i = 0; i <= m; ++i)
		init::rd(B[i].x);
	int len = 1;
	while (len <= n + m)
		len <<= 1;
	init(len);
	FFT(A, len, eps);
	FFT(B, len, eps);
	for (int i = 0; i <= len; ++i)
		A[i] = A[i] * B[i];
	FFT(A, len, ieps);
	for (int i = 0; i <= n + m; ++i)
		printf("%d ", int(A[i].x / len + 0.5));
	return 0;
}
} // namespace FFT

namespace linearBasis
{
// 线性基是竞赛中常用来解决子集异或一类题目的算法
typedef long long LL;
const int MAXL = 60;
int n;
LL a[MAXL + 5];
std::vector<LL> v;
void insert(LL t)
{
	for (int j = MAXL; j >= 0; --j)
	{
		if (!(t & (1ll << j)))
			continue;
		if (a[j])
			t ^= a[j];
		else
		{
			for (int k = 0; k < j; ++k)
				if (t & (1ll << k))
					t ^= a[k];
			for (int k = j + 1; k <= MAXL; ++k)
				if (a[k] & (1ll << j))
					a[k] ^= t;
			a[j] = t;
			return;
		}
	}
}
void move_into_vector()
{
	v.clear();
	for (int i = 0; i <= MAXL; ++i)
		if (a[i])
			v.push_back(a[i]);
}
void merge(LL *b)
{
	for (int i = 0; i <= MAXL; ++i)
		insert(b[i]);
}
LL query_MAX()
{
	LL ans = 0;
	for (int i = 0; i <= MAXL; ++i)
		ans ^= a[i];
	return ans;
}
// 询问第k小
LL query_kth(LL k)
{
	LL ans = 0;
	if ((int)v.size() != n)
		--k;
	if (k >= 1ll << v.size())
		return -1;
	for (size_t i = 0; i < v.size(); ++i)
		if (k & (1ll << i))
			ans ^= v[i];
	return ans;
}
} // namespace linearBasis

namespace SORT
{
#define mid(l, r) (((l) + (r)) >> 1)
void bubbleSort(int *a, int n)
{
	for (int i = 1; i < n; ++i)
		for (int j = n - 1; j >= i; --j)
			if (a[j] > a[j + 1])
				std::swap(a[j], a[j + 1]);
}
void selectionSort(int *a, int n)
{
	for (int i = 1; i < n; ++i)
		for (int j = i + 1; j <= n; ++j)
			if (a[i] > a[j])
				std::swap(a[i], a[j]);
}
void insertSort(int *a, int n)
{
	std::vector<int> v;
	v.push_back(a[1]);
	for (int i = 2; i <= n; ++i)
		v.insert(std::lower_bound(v.begin(), v.end(), a[i]), a[i]);
	for (int i = 1; i <= n; ++i)
		a[i] = v[i - 1];
}
void mergeSort(int *a, int n, int l, int r)
{
	if (l == r)
		return;
	int m = mid(l, r);
	mergeSort(a, n, l, m);
	mergeSort(a, n, m + 1, r);
	std::inplace_merge(a + l, a + m + 1, a + r + 1);
	// const int N = 100000;
	// int b[N];
	// int l1 = l, r1 = m + 1, l2 = m + 1, r2 = r + 1, p = l;
	// while (l1 < r1 && l2 < r2)
	// 	if (a[l1] <= a[l2])
	// 		b[p++] = a[l1++];
	// 	else
	// 		b[p++] = a[l2++];
	// while (l1 < r1)
	// 	b[p++] = a[l1++];
	// while (l2 < r2)
	// 	b[p++] = a[l2++];
	// for (int i = l; i <= r; ++i)
	// 	a[i] = b[i];
}
void quickSort(int *a, int n, int l, int r)
{
	int x = l, y = r, m = a[mid(l, r)];
	do
	{
		while (a[l] < m)
			++l;
		while (a[r] > m)
			--r;
		if (l <= r)
			std::swap(a[l++], a[r--]);
	} while (l <= r);
	if (l < y)
		quickSort(a, n, l, y);
	if (r > x)
		quickSort(a, n, x, r);
}
#undef mid
} // namespace SORT

namespace suffixSort
{
const int MAXN = 2000000;
int tax[MAXN], tp[MAXN], rak[MAXN], sa[MAXN];
// N : 后缀个数 M : 字符集大小
void redixSort(int N, int M)
{
	for (int i = 0; i <= M; ++i)
		tax[i] = 0;
	for (int i = 1; i <= N; ++i)
		++tax[rak[i]];
	for (int i = 1; i <= M; ++i)
		tax[i] += tax[i - 1];
	for (int i = N; i >= 1; --i)
		sa[tax[rak[tp[i]]]--] = tp[i];
}
void suffixSort(char *ch, int len)
{
	int M = 'z' - '0' + 1;
	for (int i = 1; i <= len; ++i)
		rak[i] = ch[i] - '0' + 1,
		tp[i] = i;
	redixSort(len, M);
	int p = 0;
	for (int w = 1; p < len; w <<= 1, M = p)
	{
		//这里的p仅为计数器
		p = 0;
		for (int i = 1; i <= w; ++i)
			tp[++p] = len - w + i;
		for (int i = 1; i <= len; ++i)
			if (sa[i] > w)
				tp[++p] = sa[i] - w;
		redixSort(len, M);
		std::swap(rak, tp); //此时tp为临时数组用于更新下次字符集和rak数组, 上一次的tp以被丢弃
		rak[sa[1]] = 1;
		//这里的p用于统计字符集大小
		p = 1;
		for (int i = 2; i <= len; ++i)
			rak[sa[i]] = (tp[sa[i]] == tp[sa[i - 1]] && tp[sa[i] + w] == tp[sa[i - 1] + w]) ? p : ++p;
	}
}
char ch[MAXN];
void run()
{
	std::cin >> (ch + 1);
	int len = strlen(ch + 1);
	suffixSort(ch, len);
}
} // namespace suffixSort

namespace KMP
{
//数组从一开始储存哦 qwq
void kmp(char *s1, char *s2, int l1, int l2, int *nxt, int *ans, int &cnt)
{
	cnt = 0;
	nxt[1] = 0;
	for (int i = 2; i <= l2; ++i)
	{
		int p = nxt[i - 1];
		while (s2[p + 1] != s2[i] && p)
			p = nxt[p];
		nxt[i] = s2[p + 1] == s2[i] ? p + 1 : 0;
	}
	int j = 0;
	for (int i = 1; i <= l1; ++i)
	{
		while (j && s1[i] != s2[j + 1])
			j = nxt[j];
		if (s1[i] == s2[j + 1])
			++j;
		if (j == l2)
			ans[++cnt] = j,
			j = nxt[j];
	}
}
} // namespace KMP

namespace manacher
{
const int N = 41000000;
void init(char *ch1, char *ch2, int len1, int &len2)
{
	len2 = 1;
	ch2[0] = '$';
	ch2[1] = '#';
	for (int i = 0; i < len1; ++i)
	{
		ch2[++len2] = ch1[i];
		ch2[++len2] = '#';
	}
}
int manachar(char *ch, int len)
{
	int l[N] = {0}, id = 0, md = 0, ans = 0;
	for (int i = 1; i <= len; ++i)
	{
		if (md > i)
			l[i] = min(md - i, l[id * 2 - i]);
		else
			l[i] = 1;
		while (ch[i - l[i]] == ch[i + l[i]])
			++l[i];
		if (i + l[i] > md)
			md = i + l[i],
			id = i;
	}
	for (int i = 1; i <= len; ++i)
		ans = max(ans, l[i]);
	return ans - 1;
}
} // namespace manacher

namespace trie
{
const int N = 100000;
struct node
{
	int son[100];
	int val;
	int x;
	int fail;
	node()
	{
		for (int i = 0; i < 100; ++i)
			son[i] = 0;
		val = x = fail = 0;
	}
} trie[N];
int head[N], nxt[N], val[N];
int x[N];
int root;
int cnt;
void add_normal(char *ch, int len)
{
	int o = root;
	for (int i = 0; i < len; ++i)
	{
		if (trie[o].son[ch[i] - '0'])
		{
			o = trie[o].son[ch[i] - '0'];
		}
		else
		{
			trie[o].son[ch[i] - '0'] = ++cnt;
			o = cnt;
		}
	}
	++trie[o].x;
}
void add_special(char *ch, int len)
{
	int o = root;
	for (int i = 0; i < len; ++i)
	{
		int p = 0;
		for (int j = head[o]; j; j = nxt[j])
			if (val[j] == ch[i])
				p = j;
		if (p)
			o = p;
		else
		{
			nxt[++cnt] = head[o];
			head[o] = cnt;
			val[cnt] = ch[i];
			o = cnt;
		}
	}
	++x[o];
}
void get_fail()
{
	const int M = N << 4;
	int qu[M + 2], l, r;
	l = r = 0;
	for (int i = '0' - '0'; i <= 'z' - '0'; ++i)
		if (trie[root].son[i])
			qu[r++] = trie[root].son[i];
	while (l != r)
	{
		int p = qu[l++];
		int t = trie[p].fail;
		if (l > M)
			l = 0;
		for (int i = '0' - '0'; i <= 'z' - '0'; ++i)
			if (trie[p].son[i])
			{
				qu[r++] = trie[p].son[i];
				if (r > M)
					r = 0;
				trie[trie[p].son[i]].fail = trie[t].son[i];
			}
			else
			{
				trie[p].son[i] = trie[t].son[i];
			}
	}
}
int Aho_Corasick_Automaton(char *ch, int len)
{
	int ans = 0;
	int o = root;
	for (int i = 0; i < len; ++i)
	{
		o = trie[o].son[ch[i] - '0'];
		for (int j = o; j && ~trie[j].x; j = trie[j].fail)
			ans += trie[j].x,
				trie[j].x = -1;
	}
	return ans;
}
} // namespace trie

namespace CG
{
#define sqr(x) ((x) * (x))
struct point
{
	double x, y;
};
struct segment
{
	point l, r;
};
inline double dis(point a, point b)
{
	return sqrt(sqr(a.x - b.x) + sqr(a.y - b.y));
}
struct circle
{
	point cen;
	double r;
};
typedef std::vector<point> polygon;
inline point make_vec(point a, point b)
{
	point x;
	x.x = b.x - a.x;
	x.y = b.y - a.y;
	return x;
}
//点积 a ⊥ b时点积为0
inline double dot(point a, point b)
{
	return a.x * b.x + a.y * b.y;
}
// 叉积 a ∥ b时叉积为0,b在a逆时针为正,否则为负
// 几何意义是四边形不等式面积
inline double cro(point a, point b)
{
	return a.x * b.y - a.y * b.x;
}
// 求多边形面积
// 逆时针储存
inline double area(polygon &a)
{
	double ans = cro(a[a.size()], a[0]);
	for (std::size_t i = 0; i < a.size(); ++i)
	{
		ans += cro(a[i], a[i + 1]);
	}
	return ans / 2;
}
// 旋转
inline void turn(point &a, double b)
{
	point t = a;
	a.x = t.x * cos(b) - t.y * sin(b);
	a.y = t.x * sin(b) - t.y * cos(b);
}
// 判断点是否在直线上
inline bool on_line(point a, segment b)
{
	return cro(make_vec(a, b.l), make_vec(a, b.r)) == 0;
}
// 判断点是否在线段上
inline bool on_segment(point a, segment b)
{
	return dis(a, b.l) + dis(a, b.r) == dis(b.l, b.r);
}
// 海伦公式
inline double heron(double a, double b, double c)
{
	double p = (a + b + c) / 2;
	return sqrt(p * (p - a) * (p - b) * (p - c));
}
#undef sqr
} // namespace CG

namespace maximumFlow
{
typedef long long LL;
const int MAX = 30000;
int n;
int cnt = 1;
int head[MAX], nxt[MAX], to[MAX], cap[MAX], flow[MAX];
int dis[MAX], cur[MAX];
int qu[(MAX << 1) + 2], ql, qr;
void insert(int u, int v, int f)
{
	nxt[++cnt] = head[u];
	to[cnt] = v;
	cap[cnt] = f;
	flow[cnt] = 0;
	head[u] = cnt;
}
bool bfs(int s, int t)
{
	for (int i = 1; i <= n; ++i)
		dis[i] = 0,
		cur[i] = head[i];
	ql = qr = 0;
	qu[qr++] = s;
	dis[s] = 1;
	while (ql != qr)
	{
		int now = qu[ql++];
		if (ql > MAX << 1)
			ql = 0;
		for (int i = head[now], v = to[i]; i; i = nxt[i], v = to[i])
			if (cap[i] > flow[i] && !dis[v])
			{
				dis[v] = dis[now] + 1;
				if (v == t)
					return true;
				qu[qr++] = v;
				if (qr > MAX << 1)
					qr = 0;
			}
	}
	return false;
}
int dfs(int u, int maxflow, int t)
{
	if (u == t)
		return maxflow;
	int ans = 0, temp;
	for (int &i = cur[u], v = to[i]; i; i = nxt[i], v = to[i])
	{
		if (cap[i] > flow[i] && dis[v] == dis[u] + 1)
		{
			temp = dfs(v, min(maxflow - ans, cap[i] - flow[i]), t);
			flow[i] += temp;
			flow[i ^ 1] -= temp;
			ans += temp;
			if (ans >= maxflow)
				break;
		}
	}
	if (!ans)
		dis[u] = -2;
	return ans;
}
LL dinic(int s, int t)
{
	LL ans = 0;
	while (bfs(s, t))
		ans += dfs(s, 0x3fffffff, t);
	return ans;
}
// 无源汇有上下界可行流
int d[MAX], k[MAX];
int main1()
{
	int m, u, v, lower, upper, s, t;
	init::rd(n, m);
	for (int i = 1; i <= m; ++i)
	{
		init::rd(u, v, lower, upper);
		d[i] = lower;
		k[u] -= lower;
		k[v] += lower;
		insert(u, v, upper - lower);
		insert(v, u, 0);
	}
	s = n + 1;
	t = n + 2;
	int sum = 0;
	for (int i = 1; i <= n; ++i)
	{
		if (k[i] < 0)
			insert(i, t, -k[i]),
				insert(t, i, 0);
		else
			insert(s, i, k[i]),
				insert(i, s, 0),
				sum += k[i];
	}
	n += 2;
	if (dinic(s, t) != sum)
		printf("NO
");
	else
		printf("YES
");
	return 0;
}
// 有源汇有上下界最大流
int main2()
{
	int m, u, v, lower, upper, s, t, ss, tt;
	init::rd(n, m, s, t);
	for (int i = 1; i <= m; ++i)
	{
		init::rd(u, v, lower, upper);
		d[i] = lower;
		k[u] -= lower;
		k[v] += lower;
		insert(u, v, upper - lower);
		insert(v, u, 0);
	}
	ss = n + 1;
	tt = n + 2;
	int sum = 0;
	for (int i = 1; i <= n; ++i)
	{
		if (k[i] < 0)
			insert(i, tt, -k[i]),
				insert(tt, i, 0);
		else
			insert(ss, i, k[i]),
				insert(i, ss, 0),
				sum += k[i];
	}
	insert(t, s, 0x3fffffff);
	insert(s, t, 0);
	n += 2;
	if (dinic(ss, tt) != sum)
		printf("please go home to sleep
");
	else
		printf("%d
", dinic(s, t));
	return 0;
}
// 有源汇有上下界最小流
int main3()
{
	int m, u, v, lower, upper, s, t, ss, tt;
	init::rd(n, m, s, t);
	for (int i = 1; i <= m; ++i)
	{
		init::rd(u, v, lower, upper);
		d[i] = lower;
		k[u] -= lower;
		k[v] += lower;
		insert(u, v, upper - lower);
		insert(v, u, 0);
	}
	ss = n + 1;
	tt = n + 2;
	int sum = 0;
	for (int i = 1; i <= n; ++i)
	{
		if (k[i] < 0)
			insert(i, tt, -k[i]),
				insert(tt, i, 0);
		else
			insert(ss, i, k[i]),
				insert(i, ss, 0),
				sum += k[i];
	}
	n += 2;
	int f = dinic(ss, tt);
	insert(t, s, 0x3fffffff);
	int p = cnt;
	insert(s, t, 0);
	f += dinic(ss, tt);
	if (f != sum)
		printf("please go home to sleep
");
	else
		printf("%d
", flow[p]);
	return 0;
}
} // namespace maximumFlow

int main()
{
}
原文地址:https://www.cnblogs.com/happyLittleRabbit/p/10065081.html