#include <iostream>

using namespace std;

int main()
{   int n , x; cin >> n >> x;
    int a[n+1] , i , st , dr , mid;
    for ( i = 1; i <= n; i++ )
        cin >> a[i];
    st = 1; dr = n;
    while ( st <= dr ){
        mid = ( st + dr ) / 2;
        if ( a[mid] <= x )
            st = mid + 1;
        else
            dr = mid - 1;
    }
    if ( a[dr] == x ) cout << dr;
    else cout << "On n'est pas";
    return 0;
}