Solution for Exercise 17-7

ex1707

#include <stdio.h>
#include <ctype.h>

int main()
{
    char input[64];
    int ch;
    int x = 0;

    printf("Type in some text: ");
    fgets(input,63,stdin);

    while(input[x] != '\n')
    {
        ch = input[x];
        if(isalpha(ch))
            ch &= 223;
        putchar(ch);
        x++;
    }
    putchar('\n');

    return(0);
}

Output

Type in some text: Math is like 8*8=64
MATH IS LIKE 8*8=64

Notes

* For my solution, I took refuge in the function isalpha() in Line 15. That test returns TRUE whenever a letter of the alphabet is encountered, FALSE otherwise.

* Remember that you need to include the ctype.h header file when you use the isalpha() function.

* Did you see on Line 17 an assignment operator is used? The &= operator allows you to write:

c &= 223;

Instead of:

c = c & 223;

* A non-CTYPE solution could be the following if statement:

if( ch>='a' && ch<='z' )

Because the bitwise AND operator affects primarily lowercase letters, only they are singled out in the if statement's expression.

Exercise ex1708 →