#include <iostream>
#include <vector>

using namespace std;

int main()
{
    int n, d;
    cin >> n >> d;
    vector<int> F;
    for (int i = 0; i < n; i++) {
        int a;
        cin >> a;
        F.push_back(a);
    }
    int megoldas = -1, maxi=0;
    bool hiba = false;
    for (int i = maxi; i < n; i++) {
        for (int j = i; j <= i + d; j++) {
            if (j < n) {
                if (F[j] > F[i]){
                    maxi = F[j];
                    hiba = true;
                }
            }
        }
        if (hiba) {
            hiba = false;
        }
        else {
            megoldas = i + 1;
            break;
        }
    }
    cout << megoldas << endl;
}