#include<cstdio>
using namespace std;
int euclid(int a,int b,int &x,int &y)
{if(b==0){x=1;y=0;return a;}
else{
int x0,y0,d;
d=euclid(b,a%b,x0,y0);
x=y0;
y=x0-(a/b)*y0;
return d;
}

}

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


      return 0;
}