Submission #367434

#	Time	Username	Problem	Language	Result	Execution time	Memory
367434		cpp219	Geppetto (COCI15_geppetto)	C++14	80 / 80	3 ms	492 KiB

geppetto

#include <bits/stdc++.h>
#define ll int
#define ld long double
#define fs first
#define sc second
using namespace std;
const ll N = 20 + 9;
const ll inf = 1e9 + 7;
typedef pair<int,int> LL;
vector<ll> g[N];
ll n,m,x,y,dd[N][N],ans,b[N];

void f(ll i){
    if (i > n){
        ans++; return;
    }
    b[i] = 0; f(i + 1);
    for (auto j : g[i]) if (b[j]) return;
    b[i] = 1; f(i + 1);
}

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    #define task "tst"
    if (fopen(task".INP","r")){
        freopen(task".INP","r",stdin);
        //freopen(task".OUT","w",stdout);
    }
    cin>>n>>m;
    while(m--){
        cin>>x>>y;
        if (dd[x][y]) continue;
        dd[x][y] = dd[y][x] = 1;
        g[max(x,y)].push_back(min(x,y));
    }
    f(1); cout<<ans;
}

Compilation message (stderr)

geppetto.cpp: In function 'int main()':
geppetto.cpp:27:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   27 |         freopen(task".INP","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 80 / 80