#include <stdlib.h>
#include <stdio.h>

int main() {  
  char str[] = "2013.999";
  printf("%s as a string.\n", str);
  printf("%.3lf as a double.\n", atof(str)); 
  return 0;
}

/** Output: 
 * 2013.999 as a string.
 * 2013.999 as a double.
 */