A
#include <bits/stdc++.h> #define PI acos(-1.0) #define mem(a,b) memset((a),b,sizeof(a)) #define TS printf("!!! ") #define pb push_back #define inf 1e9 //std::ios::sync_with_stdio(false); using namespace std; //priority_queue<int,vector<int>,greater<int>> que; get min const double eps = 1.0e-8; typedef pair<int, int> pairint; typedef long long ll; typedef unsigned long long ull; const int maxn = 3e7 + 10; const int maxm = 300; const int turn[4][2] = {{1, 0}, { -1, 0}, {0, 1}, {0, -1}}; //priority_queue<int, vector<int>, less<int>> que; //next_permutation ll mod = 1e9 + 7; int main() { string a; cin >> a; string ans; ans = a; for (int i = 1; i <= a.size(); i++) { ans += a[a.size() - i]; } cout << ans << endl; return 0; }
B
#include <bits/stdc++.h> #define PI acos(-1.0) #define mem(a,b) memset((a),b,sizeof(a)) #define TS printf("!!! ") #define pb push_back #define inf 1e9 //std::ios::sync_with_stdio(false); using namespace std; //priority_queue<int,vector<int>,greater<int>> que; get min const double eps = 1.0e-8; typedef pair<int, int> pairint; typedef long long ll; typedef unsigned long long ull; const int maxn = 3e7 + 10; const int maxm = 300; const int turn[4][2] = {{1, 0}, { -1, 0}, {0, 1}, {0, -1}}; //priority_queue<int, vector<int>, less<int>> que; //next_permutation int ans[1000005][10]; ll mod = 1e9 + 7; int getans(int x) { if (x < 10) { return x; } else { int cur = 1; while (x > 0) { if (x % 10 != 0) { cur *= x % 10; } x /= 10; } return getans(cur); } } int main() { for (int i = 1; i <= 1000001; i++) { int now = getans(i); for (int j = 1; j <= 9; j++) { ans[i][j] = ans[i - 1][j]; } ans[i][now]++; } int q; cin >> q; int l, r, k; for (int i = 1; i <= q; i++) { scanf("%d %d %d", &l, &r, &k); cout << ans[r][k] - ans[l - 1][k] << endl; } return 0; }
C
构造题 要求构造出一个数列满足下列条件
可以看成构造有向图里面的环
#include <bits/stdc++.h> #define PI acos(-1.0) #define mem(a,b) memset((a),b,sizeof(a)) #define TS printf("!!! ") #define pb push_back #define inf 1e9 //std::ios::sync_with_stdio(false); using namespace std; //priority_queue<int,vector<int>,greater<int>> que; get min const double eps = 1.0e-8; typedef pair<int, int> pairint; typedef long long ll; typedef unsigned long long ull; const int maxn = 3e7 + 10; const int maxm = 300; const int turn[4][2] = {{1, 0}, { -1, 0}, {0, 1}, {0, -1}}; //priority_queue<int, vector<int>, less<int>> que; //next_permutation int ans[1000005][10]; ll mod = 1e9 + 7; int main() { int n, a, b; cin >> n >> a >> b; int x, y; x = y = -1; int cnt = n / a; for (int i = 0; i <= cnt; i++) { if ((n - i * a) % b == 0) { x = i; y = (n - i * a) / b; break; } } if (x == -1) { cout << -1 << endl; return 0; } int cur = 0; for (int i = 1; i <= x; i++) { cout << cur + a << " "; for (int j = 1; j <= a - 1; j++) { cout << cur + j << " "; } cur += a; } for (int i = 1; i <= y; i++) { cout << cur + b << " "; for (int j = 1; j <= b - 1; j++) { cout << cur + j << " "; } cur += b; } //cout << endl; return 0; }
D
https://www.cnblogs.com/AWCXV/p/8453152.html
https://www.cnblogs.com/forever97/p/cf463.html
#include <bits/stdc++.h> #define PI acos(-1.0) #define mem(a,b) memset((a),b,sizeof(a)) #define TS printf("!!! ") #define pb push_back #define inf 1e9 //std::ios::sync_with_stdio(false); using namespace std; //priority_queue<int,vector<int>,greater<int>> que; get min const double eps = 1.0e-10; const double EPS = 1.0e-4; typedef pair<int, int> pairint; typedef long long ll; typedef unsigned long long ull; //const int maxn = 3e5 + 10; const int turn[4][2] = {{1, 0}, { -1, 0}, {0, 1}, {0, -1}}; //priority_queue<int, vector<int>, less<int>> que; //next_permutation const int N = 4e5; const int M = 20; const ll INF = 1e16; int Q; ll last, W[N + 10], sum[N + 10][M + 10]; int f[N + 10][M + 10], cnt = 1; int main() { cin >> Q; for (int i = 0; i <= 20; i++) { sum[1][i] = sum[0][i] = INF; } W[0] = INF; for(int i=1;i<=Q;i++) { ll ope, p, q; cin >> ope >> p >> q; if (ope == 1) { ll R = p ^ last, w = q ^ last; cnt++; W[cnt] = w; if (W[R] >= w) { f[cnt][0] = R; } else { ll now = R; for (int i = 20; i >= 0; i--) if (W[f[now][i]] < w) { now = f[now][i]; } f[cnt][0] = f[now][0]; } for (int i = 1; i <= 20; i++) { f[cnt][i] = f[f[cnt][i - 1]][i - 1]; } sum[cnt][0] = W[f[cnt][0]]; for (int i = 1; i <= 20; i++) { if (f[cnt][i] == 0) { sum[cnt][i] = INF; } else { sum[cnt][i] = sum[cnt][i - 1] + sum[f[cnt][i - 1]][i - 1]; } } } else { ll R = p ^ last, X = q ^ last; int len = 0; if (X < W[R]) { cout << 0 << endl; last = 0; continue; } X -= W[R]; len++; for (int i = 20; i >= 0; i--) { if (X >= sum[R][i]) { X -= sum[R][i]; R = f[R][i]; len += (1 << i); } } cout << len << endl; last = len; } } return 0; }