Submission #350162

#	Time	Username	Problem	Language	Result	Execution time	Memory
350162		juggernaut	Parachute rings (IOI12_rings)	C++14	20 / 100	4070 ms	1024 KiB

rings

#ifndef EVAL
#include"grader.cpp"
#endif
#include<bits/stdc++.h>
using namespace std;
vector<int>g[5005];
bool on[5005],vis[5005];
int n,deg[5005];
bool dfs(int v,int p){
    bool flag=false;
    vis[v]=true;
    for(int to:g[v])if(to!=p){
        if(on[to])continue;
        if(flag)return false;
        if(vis[to])return false;
        if(!dfs(to,v))return false;
        flag=true;
    }
    return true;
}
bool check(){
    for(int i=0;i<n;i++)vis[i]=0;
    for(int i=0;i<n;i++)if(!on[i]&&!vis[i]&&deg[i]<2)if(!dfs(i,i))return false;
    for(int i=0;i<n;i++)if(!vis[i]&&!on[i])return false;
    return true;
}
void Init(int N){n=N;}
void Link(int x,int y){
    g[x].push_back(y);
    g[y].push_back(x);
    deg[x]++;
    deg[y]++;
}
int CountCritical(){
    int cnt=0;
    for(int i=0;i<n;i++){
        on[i]=true;
        for(auto to:g[i])deg[to]--;
        cnt+=check();
        for(auto to:g[i])deg[to]++;
        on[i]=false;
    }
    return cnt;
}
/*
7 13
-1
1 2
-1
0 5
-1
2 0
-1
3 2
-1
3 5
-1
4 3
-1

*/

• Subtask 1: 20 / 20
• Subtask 2: 0 / 17
• Subtask 3: 0 / 18
• Subtask 4: 0 / 14
• Subtask 5: 0 / 31