// Demonstrating how to play with characters in C
// Program converts an upper case letter to a lower case letter

// Sasha Vassar Week 2, Lecture 3

// Problem: A user inputs an upper case letter, and wants 
// the computer to output the same letter, but in lower case.
// Possibilities/Breakpoints?
// Eg. input is 'C' (67), and we want to output 'c' (99)
// +32 is the difference between capital and lower case
// Solution: - 'A' to find out the distance from the first of the alphabet
// and then we add that distance to a little 'a'

#include <stdio.h>

int main(void) {
    char upper_letter;
    char lower_letter;
    int scanf_return;

    printf("Please enter an upper case letter: ");
    scanf_return = scanf(" %c", &upper_letter);
    printf("Scanf() returned %d\n", scanf_return);

    if (scanf_return != 1) {
        printf("No input was taken in, the program will now exit\n");
        return 1;
    }
    if (upper_letter >= 'A' && upper_letter <= 'Z') {
        lower_letter = upper_letter - 'A' + 'a';
        printf("The lower case letter is %c\n", lower_letter);
    } else {
        printf("YOu did not enter a capital letter\n");
         // return 1 - Program finished running but with some problems
        return 1;
    }
   
    //Program finished running with no problems 
    return 0;
}