Solution-CF490-D2-A

#include <iostream>
#include <bits/stdc++.h>
#include <math.h>

using namespace std;

int main()
{
    int n=0;
    int k=0;
    cin>>n;
    vector <int> position1;
    vector <int> position2;
    vector <int> position3;
    for(int i=1;i<=n;i++){
        cin>>k;
        if(k==1){
            position1.push_back(i);
        }
        if(k==2){
            position2.push_back(i);
        }
        if(k==3){
            position3.push_back(i);
        }
    }
    int p1=position1.size(),p2=position2.size(),p3=position3.size(),w1=0,w=0;
    w1 = min(p1,p2);
    w = min(w1,p3);
    cout<<w<<endl;
    for(int i=0;i<w;i++){
        cout<<position1[i]<<" "<<position2[i]<<" "<<position3[i]<<endl;
    }
    return 0;
}