Ha

#include <iostream>
using namespace std;

int main () {

int n, k;
cin >> n >> k;
int mp[1100]{};
for (int i = 1; i <= n; i ++) {
    int t; cin >> t; mp[t] ++;
}
int ans = 0;
while (mp[ans] != 0) {
    ans += k;
}
cout << ans << endl;

return 0;

}