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

int main(void) {
	int a,b;
	double c;
	scanf("%d%d",&a,&b);
	if(a < b){c = sqrt(b*b-a*a);}
	else if(a > b){c = sqrt(a*a-b*b);}
	else{c = sqrt(a*a+b*b);}
	printf("%lf",c);
	return 0;
}