#include <bits/stdc++.h>
using namespace std;

int main() {
    int n, s, k;
    cin >> n >> s >> k;
    int ans = -1, diff = 100;
    for (int i = 1; i <= n; i++) {
        int a;
        cin >> a;
        int d = abs(a - s);
        if (d <= k && d < diff) {
            ans = i;
            diff = d;
        }
    }
    if (ans >= 1) {
        cout << ans << endl;
    } else {
        cout << "Unlucky!" << endl;
    }
}