#include <iostream>

using namespace std;

int boldog(int a[1000], int n, int k){
    for(int i = 0; i < n; i++){
            int j = i-1;
            while((j > 0 || j > i-k) && a[j] <= a[i]){
                j--;
            }
            if(j == 0 || j == i-k){
                int u = i+1;
                while((u < i+k || u < n) && a[j] <= a[i]){
                    u++;
                }
                if(u == i+k || u == n){
                    return i+1;
                }
            }
    }
    return -1;
}

int main()
{
    int a[1000], n, k;
    cin >> n >> k;

    for(int i = 0; i < n; i++){
        cin >> a[i];
    }

    cout << boldog(a, n, k);


    return 0;
}