package baekjoon.이분탐색;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
class Main1300 {
static int N, K;
public static void main(String[] args) throws Exception {
input();
go();
}
private static void go() {
long L = 1, R = (long)N * N, ans = 0;
while (L <= R) {
long mid = (L + R) / 2;
if (determination(mid)) {
ans = mid;
R = mid - 1;
} else {
L = mid + 1;
}
}
System.out.println(ans);
}
private static boolean determination(long mid) {
long cnt = 0;
for (int i = 1; i <= N; i++) {
cnt += Math.min(N, mid / i);
}
return cnt >= K;
}
private static void input() throws IOException {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
N = Integer.parseInt(br.readLine());
K = Integer.parseInt(br.readLine());
}
}
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