Submission #1274451

#	Time	Username	Problem	Language	Result	Execution time	Memory
1274451		hccoder	Permutation Game (APIO25_permgame)	C++20	30 / 100	3 ms	348 KiB

permgame

#include <bits/stdc++.h>
using namespace std;

int Bob(std::vector<int> t);


int Alice(int m, int e, std::vector<int> u, std::vector<int> v, int n, std::vector<int> p){
    if (m==2){
        map<int, int> mp;
        for (int i = 0; i<n; i++) mp[p[i]] = i;
        for (int i = 0; i<n; i++){
            if (p[i]!=i){
                int x = mp[i];
                Bob({i, x});
                mp[p[i]] = x;
                mp[i] = i;
                swap(p[i], p[x]);
            }
        }
        return n;
    }
    else if (m==3 && e==3){
        int res = 0;
        vector<int> vis(n);
        for (int i = 0; i<n; i++){
            int j = i;
            int cnt = 0;
            while (!vis[j]){
                vis[j] = 1;
                j = p[j];
                cnt++;
            }
            if (cnt & 1) res++;
        }
        for (int i = 0; i<10*n; i++){
            for (int j = 0; j<n; j++){
                int x = p[j];
                int y = p[x];
                int z = p[y];
                if (x!=y && y!=z && x!=z) {
                    vector<int> h{x, y, z};
                    int r = Bob(h);
                    int a = h[v[r]], b = h[u[r]];
                    swap(p[a], p[b]);
                    break;
                }
            }
        }
        return res;
    }
}

Compilation message (stderr)

permgame.cpp: In function 'int Alice(int, int, std::vector<int>, std::vector<int>, int, std::vector<int>)':
permgame.cpp:51:1: warning: control reaches end of non-void function [-Wreturn-type]
   51 | }
      | ^

• Subtask 0: 0 / 0
• Subtask 1: 6 / 6
• Subtask 2: 0 / 6
• Subtask 3: 0 / 10
• Subtask 4: 24 / 24
• Subtask 5: 0 / 24
• Subtask 6: 0 / 30