C/math.h/hypot
hypot: return the square root of the sum of the squares of side1 and side2
//Declaration: float hypotf(float side1, float side2);
double hypot(double side1, double side2);
long double hypotl(long double side1, long double side2);
#include <math.h>
#include <stdio.h>
int main(void)
{
int e;
double f;
f = hypotf(3, 4);
printf("%f", f);
}
/*5.000000*/