Converting uppercase to lowercase : char Calculation « Data Type « C Tutorial

1. C Tutorial
2. Data Type
3. char Calculation

#include <stdio.h>

int main(void)
{
  char letter = 'B';                        


  if(letter >= 'A')                       
    if (letter <= 'Z'){                                     
      letter = letter - 'A'+ 'a';         
      printf("You entered an uppercase %c\n", letter);
    }
    else                                  
      printf("Try using the shift key, Bud! I want a capital letter.\n");
  return 0;
}

You entered an uppercase b