Submission #1195590

#	Time	Username	Problem	Language	Result	Execution time	Memory
1195590		vnedu	전압 (JOI14_voltage)	C++17	10 / 100	213 ms	4164 KiB

voltage

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;

template<class T> bool maximize(T &a, const T &b){ return (a < b ? a = b, 1 : 0); }
template<class T> bool minimize(T &a, const T &b){ return (a > b ? a = b, 1 : 0); }

#define fi first
#define se second

#define pb push_back
#define ii pair<int, int>

#define all(x) x.begin(), x.end()

#define TASK "nonsense"

/// end of template ///

const int N = 1e5 + 10;
const int M = 2e5 + 10;
int n,m;
ii edge[M];
vector<int> adj[N];
namespace sub1
{
    bool check()
    {
        return (n<=1000 && m<=2000);
    }
    const int N = 1e3 + 10;
    bool vis[N];
    int dep[N];
    void dfs(int u)
    {
        vis[u]=1;
        for(int v : adj[u]) if(!vis[v])
        {
            dep[v]=dep[u]+1;
            dfs(v);
        }
    }
    void solve()
    {
        int ans=0;
        for(int tri=1;tri<=m;++tri)
        {
            for(int i=0;i<=n;++i) vector<int>().swap(adj[i]);
            for(int i=1;i<=m;++i) if(i!=tri)
            {
                int u=edge[i].fi,v=edge[i].se;
                adj[u].pb(v);
                adj[v].pb(u);
            }
            adj[0].pb(edge[tri].fi);
            adj[edge[tri].fi].pb(0);
            adj[0].pb(edge[tri].se);
            adj[edge[tri].se].pb(0);
            memset(vis,0,sizeof(vis));
            for(int i=0;i<=n;++i) if(!vis[i])
            {
                dep[i]=1;
                dfs(i);
            }
            bool ok=1;
            edge[0]={0,edge[tri].fi};
            edge[m+1]={0,edge[tri].se};
            for(int i=0;i<=m+1;++i) if(i!=tri)
            {
                int du=dep[edge[i].fi];
                int dv=dep[edge[i].se];
                ok&=((du&1)!=(dv&1));
            }
            ans+=ok;
        }
        cout<<ans;
    }
}
void solve()
{
    cin>>n>>m;
    for(int i=1;i<=m;++i) cin>>edge[i].fi>>edge[i].se;
    if(sub1::check()) return void(sub1::solve());
}
int main()  {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

//    freopen(TASK".inp","r",stdin);
//    freopen(TASK".out","w",stdout);

    int testcase=1;
//    cin>>testcase;

    while (testcase--)
        solve();

    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 0 / 10
• Subtask 3: 0 / 35
• Subtask 4: 0 / 45