// lp0227.c

// C program for implementation of ftoa()
#include <stdio.h>
#include <math.h>
#include <float.h>
#include <stdlib.h>
 
// reverses a string 'str' of length 'len'
void reverse(char *str, int len){
  int i=0, j=len-1, temp;
  while (i<j)
    {
      temp = str[i];
      str[i] = str[j];
      str[j] = temp;
      i++; j--;
    }
}
 
 // Converts a given integer x to string str[].  d is the number
 // of digits required in output. If d is more than the number
 // of digits in x, then 0s are added at the beginning.
int intToStr(int x, char str[], int d){
  int i = 0;
  while (x)
    {
      str[i++] = (x%10) + '0';
      x = x/10;
    }
 
  // If number of digits required is more, then
  // add 0s at the beginning
  while (i < d)
    str[i++] = '0';
  
  reverse(str, i);
  str[i] = '\0';
  return i;
}
 
// Converts a floating point number to string.
void ftoa(float n, char *res, int afterpoint)
{
  // Extract integer part
  int ipart = (int)n;
  
  // Extract floating part
  float fpart = n - (float)ipart;
  
  // convert integer part to string
  int i = intToStr(ipart, res, 0);
  
  // check for display option after point
  if (afterpoint != 0)
    {
      res[i] = '.';  // add dot
 
      // Get the value of fraction part upto given no.
      // of points after dot. The third parameter is needed
      // to handle cases like 233.007
      fpart = fpart * pow(10, afterpoint);
      
      intToStr((int)fpart, res + i + 1, afterpoint);
    }
}


int main(int argc, char ** argv)
{

  double f;
  char buf[200];

  f = DBL_MAX;
  printf("The biggest double: %f\n", f);
  
  for (int j = 1; j < argc; j++){
    printf("argv[%d] %s %f\n", j, argv[j], atof(argv[j]));
  }
  
  printf("\nExamples of ftoa code:\n");
  for (int i = 0; i < 10; i++){
    f = i * .5;
    ftoa(f, buf, 2);
    printf( "%d: %f  %s\n", i, f, buf);
  }
  return 0;
}