text: // calculate absolute numbers
  
  #include <stdio.h>
  
  float absoluteValue (float x)
  {
      if ( x < 0)
      x = -x;
  
      return x;
  }
  
  int main(int argc, char const *argv[])
  {
      float f1 = - 15.5;
  
      float result;
  
      result = absoluteValue(f1);
      printf("absolute value of %f = %f", f1,result);
  
      return 0;
  }
  