Finding inverse

#include <bits/stdc++.h>

using namespace std;

//Definitions for quicker writing
#define REP(i,a,b) for (int i = a; i < b; i++)
#define clz __builtin_clz
#define ctz __builtin_ctz
#define popct __builtin_popcount
#define PB push_back
#define MP make_pair
#define F first
#define S second
#define X real()
#define Y imag()

//Typedefs for quicker writing
typedef long long ll;
typedef vector<int> vi;
typedef vector<long long> vl;
typedef pair<int,int> pi;
typedef pair<long long, long long> pl;
typedef complex<long long> po;

//Max values
const long long lmx = LLONG_MAX;
const int imx = INT_MAX;

int main() {
	//IO optimization
	ios::sync_with_stdio(0);
	cin.tie(0);
	
	//Input definition
	ll a,m;

	//Read In
	cin >> a >> m;

	//Main part
	ll res;
    if((m+1)%a==0) res = (m+1)/a;
    else res = -1;

	//Write out
	cout << res << "\n";
		
	//Return
	return 0;

}

Test 1

Verdict: WRONG ANSWER

Test 2

Verdict: RUNTIME ERROR

Test 3

Verdict: WRONG ANSWER

Test 4

Verdict: WRONG ANSWER

Test 5

Verdict: RUNTIME ERROR

Test 6

Verdict: WRONG ANSWER

Test 7

Verdict: WRONG ANSWER

Test 8

Verdict: ACCEPTED

Test 9

Verdict: WRONG ANSWER

Test 10

Verdict: WRONG ANSWER

Test 11

Verdict: ACCEPTED

Test 12

Verdict: WRONG ANSWER

Test 13

Verdict: WRONG ANSWER

Test 14

Verdict: ACCEPTED