RelexBsearch

#include<stdio.h>
#include<iostream>
#include<algorithm>
using namespace std;
typedef long long int ll;

int Bsearch(int l,int r,ll key,pair<ll,int> arr[]){
    int m = (l+r)/2;
    if(arr[m].first == key){
        int j = m;
        while(arr[j-1].first == key){
            j--;
        }
        return arr[j].second;
    }
    if(l > r)return -1;

    if(arr[m].first > key){
        return Bsearch(l,m-1,key,arr);
    }else{
        return Bsearch(m+1,r,key,arr);
    }
}

int main()
{
    int n;
    scanf("%d",&n);

    pair<ll,int> arr[n+1];arr[0] = {-2e9,0};
    for(int i=1;i<=n;i++){
        ll x;
        scanf("%lld",&x);
        arr[i] = {x,i};
    }
    sort(arr+1,arr+n+1);
    ll m;
    scanf("%lld",&m);

    for(int i=0;i<m;i++){
        ll key;
        scanf("%lld",&key);

        int index = Bsearch(1,n,key,arr);
        if(index != -1){
            printf("%d\n",index);
        }else{
            printf("Not found\n");
        }
    }
    return 0;
}