Submission #153080

#	Time	Username	Problem	Language	Result	Execution time	Memory
153080		Mercenary	Potemkin cycle (CEOI15_indcyc)	C++14	0 / 100	9 ms	632 KiB

indcyc

#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/trie_policy.hpp>

#define pb push_back
#define mp make_pair
#define taskname "A"

using namespace std;
using namespace __gnu_pbds;

typedef long long ll;
typedef long double ld;
typedef pair<int,int> ii;
typedef tree <int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;

const int maxn = 1e3 + 5;
bitset<maxn> s[maxn] , l[maxn];
int n , m;
int u[maxn] , v[maxn];

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    if(fopen(taskname".INP","r")){
		freopen(taskname".INP", "r",stdin);
		freopen(taskname".OUT", "w",stdout);
    }
    cin >> n >> m;
    for(int i = 0 ; i < m ; ++i){
        int u , v;cin >> u >> v;--u;--v;
//        if(u == v)continue;
        ::u[i] = u;::v[i] = v;
        s[u].set(v , 1);
        s[v].set(u , 1);
    }
    for(int i = 0 ; i < n ; ++i)s[i][i] = 1;
    for(int i = 0 ; i < n ; ++i){
        for(int j = 0 ; j < maxn ; ++j){
            s[i][j] = !s[i][j];
        }
    }
    for(int i = 0 ; i < m ; ++i){
        l[u[i]] |= (s[v[i]]);
        l[v[i]] |= (s[u[i]]);
    }
    for(int i = 0 ; i < n ; ++i){
        l[i] &= s[i];
    }
    for(int i = 0 ; i < n ; ++i){
        l[i].set(i , 0);
        for(int j = 0 ; j < maxn ; ++j){
            s[i][j] = !s[i][j];
        }
    }
//    for(int i = 0 ; i < n ; ++i)s[i][i] = 0;
    for(int i = 0 ; i < m ; ++i){
        int u = ::u[i];
        int v = ::v[i];
//        cout << u + 1 << " " << v + 1 << endl;
//        cout << l[u].test(v) << " " << (l[u] & s[v]).count() << endl;
//        for(int j = 0 ; j < n ; ++j){
//            if((l[u] & s[v]).test(j))cout << j + 1 << endl;
//        }
//        cout << endl;
        if((l[u] & s[v]).count() >= 1){
            for(int i = 0 ; i < n ; ++i){
                for(int j = 0 ; j < n ; ++j){
                    if(!s[i].test(v) && !s[j].test(u) && s[v].test(j) && s[i].test(u) && !s[i][j]){
                        return cout << i + 1 << " " << u + 1 << " " << v + 1 << " " << j + 1 , 0;
                    }
                }
            }
        }
    }
    cout << "no";
}

Compilation message (stderr)

indcyc.cpp: In function 'int main()':
indcyc.cpp:27:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   freopen(taskname".INP", "r",stdin);
   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
indcyc.cpp:28:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   freopen(taskname".OUT", "w",stdout);
   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

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