#include<cstdio>
void euclid(int a,int b,int *d,int *x,int *y){
   if(b==0){
      *d=a;
      *x=1;
      *y=0;
   }else{
      int x0,y0;
      euclid(b,a%b,d,&x0,&y0);
      *x=y0;
      *y=x0-(a/b)*y0;
   }
}
int main(){
   int a,n,x,y,d;
   freopen("inversmodular.in","r",stdin);
   freopen("inversmodular.out","w",stdout);
   scanf("%d%d",&a,&n);
   euclid(n,a,&d,&x,&y);
   while(y<0)
      y+=n;
   y%=n;
   printf("%d",y);
   return 0;
}