/*Input a postive integer n and check if it is a factorial of some
*integer m or not. If yes, print m, otherwise, print "NO".
*author:rahule@cse.iitk.ac.in
*/

#include<stdio.h>
int main()
{
	double m,n,fact=1,i;
	printf("\nenter n and m :");    //enter n , m
	scanf("%lf%lf",&n,&m);
	for(i=1;i<=m;i++)		//finding the factorial of m in "fact"
		fact=fact*i;
	if(fact==n)			//checkiing if factorial is equal to n
		printf("\nthe factorial is %lf",n);
	else
		printf("\nNO");
	printf("\n");
}