Submission #246548

#	Time	Username	Problem	Language	Result	Execution time	Memory
246548		dantoh000	Potemkin cycle (CEOI15_indcyc)	C++14	50 / 100	94 ms	4856 KiB

indcyc

#include <bits/stdc++.h>
using namespace std;
int n,m;
int id[1005][1005];
int A[1005];
int B[1005];
int vis[100005];
vector<int> ans;
int cycle;
bool dfs(int a, int b){

    vis[id[a][b]] = 2;
    for (int c = 1; c <= n; c++){
        if (c != a && id[b][c] && !id[a][c]){
            if (vis[id[b][c]] == 2){
                cycle = b;
                ans.push_back(b);
                ans.push_back(a);
                return true;
            }
            else if (dfs(b,c)){
                ans.push_back(a);
                if (id[a][cycle]){
                    for (auto x : ans) printf("%d ",x);
                    exit(0);
                }
                return true;
            }

        }
    }
    vis[id[a][b]] = 1;
    return false;
}
int main(){
    scanf("%d%d",&n,&m);
    for (int i = 1; i <= m; i++){
        scanf("%d%d",&A[i],&B[i]);
        id[B[i]][A[i]] = id[A[i]][B[i]] = i;
    }
    for (int i = 1; i <= m; i++){
        if (vis[i] == 0) {
            dfs(A[i],B[i]);
        }
    }

    printf("no");
}

Compilation message (stderr)

indcyc.cpp: In function 'int main()':
indcyc.cpp:36:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d",&n,&m);
     ~~~~~^~~~~~~~~~~~~~
indcyc.cpp:38:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d",&A[i],&B[i]);
         ~~~~~^~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 0 / 10
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 10
• Subtask 10: 0 / 10