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

int main(void)
{
double x1=1, y1=5, x2=4, y2=7,
side_1, side_2, distance;

side_1 = x2 _ x1;
side_2 = y2 _ y1;
distance = sqrt(side_1*side_1 + side_2*side_2);

printf("The distance between the two points is"
       "%5.2f\n:",distance);

return 0;
}

여기 잘못된곳이 어디죠???