kusac

#include <iostream>
using namespace std;
int N, M;

int gcd(int a, int b){return b==0?a:gcd(b, a%b);}

int main(){
  cin >> N >> M;
  int g=gcd(N, M);
  M/=g;
  cout << g*(M-1) << "\n";
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED