// simplified chapter1_1.c using pythag function
//
#include <stdio.h>
#include <math.h>

double pythag( double a, double b)
{
  return sqrt( a*a + b*b);
}

int main(void)
{
   double x1 = 1.1, y1 = 5.5, x2 = 4.4, y2 = 7.7, d;

   d = pythag( x2-x1, y2-y1);

   printf( "d = %g\n", d);

   return 0;
}