6-11 using the function to calculate the distance between two points (10 points)

This problem required to achieve a function, given any two points on a plane coordinate (x 1, y 1) and (x 2, y 2), find the distance between the two points .

Function interface definition:

double dist( double x1, double y1, double x2, double y2 );

Wherein the parameters passed to the user coordinates of two points (x1, y1) plane and (x2, y2), the distance between two points dist function should return.

Referee test program Example:

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

double dist( double x1, double y1, double x2, double y2 );

int main()
{    
    double x1, y1, x2, y2;

    scanf("%lf %lf %lf %lf", &x1, &y1, &x2, &y2);
    printf("dist = %.2f\n", dist(x1, y1, x2, y2));

    return 0;
}

/* 你的代码将被嵌在这里 */

Sample input:

10 10 200 100

Sample output:

dist = 210.24

double dist( double x1, double y1, double x2, double y2 )
{
	double i,j,s;
	i=(x1-x2)*(x1-x2);
	j=(y1-y2)*(y1-y2);
	s=pow(i+j,0.5);
	return s;
}