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Submission #791463

# Submission time Handle Problem Language Result Execution time Memory
791463 2023-07-24T06:47:16 Z ttamx Star Trek (CEOI20_startrek) C++14
0 / 100
 0 ms 340 KB 
#include<bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef long double ld;

const int N=1005;
const ll mod=1e9+7;

ll binpow(ll a,ll b){
    ll res=1;
    while(b>0){
        if(b&1)res*=a,res%=mod;
        a*=a,a%=mod;
        b>>=1;
    }
    return res;
}

int n;
ll d,ans,sum;
vector<int> adj[N];
ll dp[N][2];

bool dfs(int u,int p){
    bool res=true;
    bool ok=true;
    for(auto v:adj[u]){
        if(v==p)continue;
        ok=false;
        res&=dfs(v,u);
    }
    res^=true;
    return res|ok;
}

bool dfs2(int u,int p,int t,bool w){
    bool res=true;
    bool ok=true;
    for(auto v:adj[u]){
        if(v==p)continue;
        ok=false;
        res&=dfs2(v,u,t,w);
    }
    if(u==t){
        ok=false;
        res&=w;
    }
    res^=true;
    return res|ok;
}
int main(){
    cin.tie(nullptr)->sync_with_stdio(false);
    cin >> n >> d;
    for(int i=1;i<n;i++){
        int u,v;
        cin >> u >> v;
        adj[u].emplace_back(v);
        adj[v].emplace_back(u);
    }
    for(int i=1;i<=n;i++)sum+=dfs(i,i);
    for(int i=1;i<=n;i++)ans+=sum*dfs2(1,1,i,true)+(n-sum)*dfs2(1,1,i,false);
    cout << ans;
}

Subtask #1
0 / 0.0

# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 340 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #2
0 / 7.0

# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 340 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
0 / 8.0

# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 340 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 15.0

# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 340 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #5
0 / 15.0

# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 340 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #6
0 / 20.0

# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 340 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #7
0 / 20.0

# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 340 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #8
0 / 15.0

# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 340 KB Output isn't correct
2 Halted 0 ms 0 KB -