Submission #870656

#	Time	Username	Problem	Language	Result	Execution time	Memory
870656		TheSahib	Paths (BOI18_paths)	C++14	Compilation error	0 ms	0 KiB

paths

#include <bits/stdc++.h>
 
using namespace std;
 
#define ll long long
#define pii pair<int, int>
#define oo 1e18
 
const int MAX = 3e5 + 5;
 
vector<int> g[MAX];
 
ll dp[33][MAX];
int c[MAX];
int n, m, k;
 
ll rec(int node, int mask){
	mask |= (1 << c[node]);
  	if(dp[mask][node] != -1) return dp[mask][node];
    
    ll ans = 0;
    if(__popcount(mask) >= 2) ans++;
    for(int to : g[node]){
        if(mask & (1 << c[to])){
            continue;
        }
        ans += rec(to, mask);
    }
    return dp[mask][node] = ans;
}
 
int main(){
    memset(dp, -1, sizeof(dp));
    cin >> n >> m >> k;
    for(int i = 1; i <= n; i++){
        cin >> c[i];
        c[i]--;
    }
    for(int i = 1; i <= m; i++){
        int a, b; cin >> a >> b;
        g[a].push_back(b);
        g[b].push_back(a);
    }
    ll ans = 0;
    for(int i = 1; i <= n; i++){
        ans += rec(i, 0);
    }
    cout << ans << '\n';
}

Compilation message (stderr)

paths.cpp: In function 'long long int rec(int, int)':
paths.cpp:22:8: error: '__popcount' was not declared in this scope
   22 |     if(__popcount(mask) >= 2) ans++;
      |        ^~~~~~~~~~