#include <iostream>
#include <cstdio>
using namespace std;

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

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