Submission #206893

#	Time	Username	Problem	Language	Result	Execution time	Memory
206893		oko	Paths (BOI18_paths)	C++14	70 / 100	591 ms	211272 KiB

paths

#include<bits/stdc++.h>
using namespace std;
const long long mod=1e9+7;
long long n,m,k,a[300005],ans,dp[300005][40],vis[300005][40];
vector<int>gr[300005];
long long dfs(int x,int mask)
{
    long long num=0;
    if(vis[x][mask])return dp[x][mask];
    vis[x][mask]=1;
    for(int i=0;i<gr[x].size();i++)
    {
        int u=gr[x][i];
        if((mask&(1<<a[u])))continue;
        num+=dfs(u,(mask|(1<<a[u])));
    }
    return dp[x][mask]=num+1;
}
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    //freopen(".in","r",stdin);
    //freopen(".out","w",stdout);
    cin>>n>>m>>k;
    for(int i=1;i<=n;i++)cin>>a[i];
    for(int i=0;i<m;i++)
    {
        int x,y;
        cin>>x>>y;
        gr[x].push_back(y);
        gr[y].push_back(x);
    }
    for(int i=1;i<=n;i++)ans+=dfs(i,(1<<a[i]));
    cout<<ans-n;
}

Compilation message (stderr)

paths.cpp: In function 'long long int dfs(int, int)':
paths.cpp:11:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i=0;i<gr[x].size();i++)
                 ~^~~~~~~~~~~~~

• Subtask 1: 23 / 23
• Subtask 2: 20 / 20
• Subtask 3: 27 / 27
• Subtask 4: 0 / 30