题目链接
题解
本来这题树上主席树暴力启发式合并就完了
结果把lca写错了...
以后再也不这么写了
复杂度(O(nlog^2n))
"for(int i = 0;dad[x][i];++ i) dad[x][i+1] = dad[dad[x][i]][i]"
De了两个多小时....QAQ
代码
#include<cstdio>
#include<cstring>
#include<algorithm>
inline int read() {
int x = 0,f = 1;
char c = getchar();
while(c < '0' || c > '9') {if(c == '-')f = -1;c = getchar(); }
while(c <= '9' && c >= '0')x = x * 10 + c - '0',c = getchar();
return x * f;
}
const int maxn = 100007;
struct NNnode {
int v,next;
} edge[maxn << 2];
int num = 0,head[maxn];
inline void add_edge(int u,int v) {
edge[++ num].v = v; edge[num].next = head[u]; head[u] = num;
}
int root[maxn],val[maxn],n,m,t,MX;
int tot = 0;
int ls[40000000],rs[40000000],cnt[40000000];
void insert(int pre,int &now,int l,int r,int key) {
cnt[++ tot] = cnt[now]; now = tot;
++ cnt[now];
if(l == r) return ;
int mid = l + r >> 1;
ls[now] = ls[pre]; rs[now] = rs[pre];
if(key <= mid) insert(ls[pre],ls[now],l,mid,key);
else insert(rs[pre],rs[now],mid + 1,r,key);
}
int query(int t1,int t2,int t3,int t4,int l,int r,int k) {
if (l == r) return l;
int mid = l + r >> 1;
int dtl = cnt[ls[t1]] + cnt[ls[t2]] - cnt[ls[t3]] - cnt[ls[t4]];
if(k <= dtl) return query(ls[t1],ls[t2],ls[t3],ls[t4],l,mid,k);
else return query(rs[t1],rs[t2],rs[t3],rs[t4],mid + 1,r,k - dtl);
}
int root_num[maxn],siz[maxn], dep[maxn],dad[maxn][25];
void dfs(int x) {
siz[x] = 1;
for(int i = 1;i < 20;++i)
dad[x][i] = dad[dad[x][i - 1]][i - 1];
insert(root[dad[x][0]],root[x],1,MX,val[x]);
for(int i = head[x];i;i = edge[i].next) {
int v = edge[i].v;
if(v == dad[x][0]) continue;
root_num[v] = root_num[x];
dad[v][0] = x; dep[v] = dep[x] + 1;
dfs(v);
siz[x] += siz[v];
}
}
int LCA(int x,int y) {
if(dep[x] > dep[y]) std::swap(x,y);
for(int i = 19;i >= 0;i --) if(dep[dad[y][i]] >= dep[x]) y = dad[y][i];
if(x == y) return x;
for(int i = 19;i >= 0;i --) if(dad[y][i] != dad[x][i]) y = dad[y][i],x = dad[x][i];
return dad[x][0];
}
int work_q(int x,int y,int k) {
int lca = LCA(x,y);
int F_lca = dad[lca][0];
return query(root[x],root[y],root[lca],root[dad[lca][0]],1,MX,k);
}
void work_L(int x,int y) {
//printf("%d ***** %d
",x,y);
if(siz[root_num[x]] < siz[root_num[y]]) std::swap(x,y);
dad[y][0] = x;
siz[root_num[x]] += siz[root_num[y]];
root_num[y] = root_num[x];
dep[y] = dep[x] + 1; add_edge(x,y);add_edge(y,x);
dfs(y);
}
int b[maxn];
void solve() {
tot = MX = 0;
n = read(),m = read(); t = read();
for(int i = 1;i <= n;++ i) b[i] = val[i] = read(),MX = std::max(val[i],MX);
std::sort(b + 1,b + n + 1);
int len = std::unique(b + 1,b + n + 1) - b - 1;
for(int i = 1;i <= n;++ i) val[i] = std::lower_bound(b + 1,b + len + 1,val[i]) - b,MX = std::max(val[i],MX);
for(int x,y,i = 1;i <= m;++ i) {
x = read(), y = read();
add_edge(x,y) , add_edge(y,x);
}
for(int i = 1;i <= n;++ i)
if(!root_num[i]) root_num[i] = i,dep[i] = 1,dfs(i);
char opt[20];
int lans = 0;
while(t --) {
scanf("%s",opt + 1) ;
if(opt[1] == 'Q') {
int x = read() ^ lans,y = read() ^ lans, k = read() ^ lans;
//printf("%d **** %d *** %d *** &&&
",x,y,lans);
printf("%d
",lans = b[work_q(x,y,k)]);
} else {
int x = read() ,y = read() ;
x ^= lans,y ^= lans;
//printf("%d **** %d *** %d *** ***
",x,y,lans);
work_L(x,y);
}
}
}
int main() {
int testcase = read(); //whattttt the fucccck？
testcase = 1;
for(int i = 1;i <= testcase;++ i) solve();
}