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

double myabs(double a, double b){

	double abs;
	abs = sqrt(a*a+b*b);
	return abs;
}

int main(void){

	double a,b;

	printf("Input a+bi\n");
	printf("a:");
	scanf("%lf",&a);
	printf("b:");
	scanf("%lf",&b);
	printf("myabs(%f%+fi)=%f\n",a,b,myabs(a,b));
	return 0;

}