BS_01

#include<bits/stdc++.h>

using namespace std;

int main()
{
  //  freopen("in.txt", "r", stdin);
  //  freopen("Out.txt", "w", stdout);

    int a[10000];
    int n;
    scanf("%d", &n);
    for(int i=0;i<n;i++)
        scanf("%d", &a[i]);

   // cout<<"The number, you want to find out: ";
    int key;
    scanf("%d", &key);

    int l=0;
    int h=n-1;
    int mid;
    int temp=0;
    int idx;

    while(l<=h){
        mid=(l+h)/2;
        if(a[mid]==key){
            idx=mid;
            h=mid-1;
            temp=1;
        }
        else if(a[mid]<key){
            l=mid+1;
        }
        else{
            h=mid-1;
        }
    }
    printf("index=%d\n", idx);
    if(temp!=1)
        printf("Paini :/\n");

    return 0;
}