Submission #357295

#	Time	Username	Problem	Language	Result	Execution time	Memory
357295		daniel920712	Parachute rings (IOI12_rings)	C++14	0 / 100	4048 ms	44804 KiB

rings

#include <stdio.h>
#include <stdlib.h>
#include <vector>
using namespace std;
int N;
int who;
vector < int > Next[1000005];
int deg[1000005];
int big[1000005];
int con[1000005];
int tt=0;
bool have[1000005];
int ok=1;
void Init(int N_)
{
    N = N_;
}

void Link(int A, int B)
{
    Next[A].push_back(B);
    Next[B].push_back(A);
    if(deg[A]==2)
    {
        tt++;
        con[B]++;
    }
    if(deg[A]==3) con[B]--;
    if(deg[B]==2)
    {
        tt++;
        con[A]++;
    }
    if(deg[B]==3) con[A]--;
    deg[A]++;
    deg[B]++;
    big[A]=max(big[A],deg[B]);
    big[B]=max(big[B],deg[A]);
}
void F(int here)
{
    int t=0;
    have[here]=1;
    for(auto i:Next[here]) if(!have[i]&&i!=who) F(i);
}
int CountCritical()
{
    int ans=0;
    int i,j;
    for(i=0;i<N;i++)
    {
        ok=1;
        who=i;
        if(tt-con[i]-(deg[i]>=3)) continue;
        for(auto j:Next[i]) deg[j]--;
        if(ok)
        {
            for(j=0;j<N;j++) have[j]=0;
            have[i]=1;
            for(j=0;j<N;j++)
            {
                if(deg[j]==0) have[j]=1;
                if(deg[j]==1&&!have[j]) F(j);
                if(deg[j]>=3&&i!=j) ok=0;
            }
            for(j=0;j<N;j++) if(!have[j]) ok=0;
        }

        for(auto j:Next[i]) deg[j]++;
        ans+=ok;
    }
    return ans;

}

Compilation message (stderr)

rings.cpp: In function 'void F(int)':
rings.cpp:42:9: warning: unused variable 't' [-Wunused-variable]
   42 |     int t=0;
      |         ^

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