#include<stdio.h>
#include<math.h>

void euclid(long long a, long long b, long long *d, long long *x, long long *y){
    if (b == 0) {
        *d = a;
        *x = 1;
        *y = 0;
    } else {
        long long x0, y0;
        euclid(b, a % b, d, &x0, &y0);
        *x = y0;
        *y = x0 - (a / b) * y0;
    }
}


int main(){
	long long A,N;
	FILE* f= fopen("inversmodular.in","rt");
	FILE* g= fopen("inversmodular.out","wt");
	fscanf(f,"%lld %lld",&A,&N);

	long long d,x,y;
	euclid(A,N,&d,&x,&y);

	x=x%N;
	if(x<0)
		x+=N;
	fprintf(g,"%lld",x);
	
	fclose(g);
	fclose(f);
	return 0;
}