#include <stdio.h>

using namespace std;

void inv(int a, int b, long long &x, long long &y){
    if(!b){
        x = 1;
        y = 0;
    }else{
        inv(b, a%b, x, y);
        long long aux = x;
        x = y;
        y = aux-(a/b)*y;
    }
}

int main(){
    freopen("inversmodular.in", "r", stdin);
    freopen("inversmodular.out", "w", stdout);
    int A, N;
    long long x = 0, y;
    scanf("%d %d", &A, &N);
    inv(A, N, x, y);
    if(x < 0)
        x = N + x % N;
    printf("%d\n", x);
    return 0;
}