#include <iostream>

using namespace std;

///cautare biara implementata recursiv
int CautBin(int st, int dr, int a[], int x)
{
    if(st>dr)
        return -1;
    int mijl = (st+dr)/2;
    if(a[mijl]==x)
        return mijl;
    if(a[mijl] < x)
        return CautBin(mijl+1, dr, a, x);
    //a[mijl] > x
    return CautBin(st, mijl-1, a, x);
}

int main()
{
    int a[] = {0,1,2,3,3,6,9,10,22,50};
    //           1 2 3 4 5 6  7  8  9
    cout<<CautBin(1,9,a,-22);
    return 0;
}