MA FUTTTTTTTTTTTTT

#include <bits/stdc++.h>
using namespace std;
ifstream f("izolate.in");
ofstream g("izolate.out");
int i,j,k,v[1001],a[1001][101],ok,p,n,m,d[101];
int main()
{
    f>>n;
    while(f>>i>>j)
    {
        a[i][j]=a[j][i]=1;
    }
    for(i=1; i<=n; i++)
    {
        d[i]=0;
        for(j=1; j<=n; j++)
            if(a[i][j]==1)
                d[i]++;
    }
    for(i=1; i<=n; i++)
    {
            if(d[i]==0)
                ok++;
    }
    g<<ok<<" ";
    for(i=1; i<=n; i++)
        if(d[i]==0)
        g<<i<<" ";
    return 0;
}