C/C++の宿題を片付けます 52代目

>>603
#include <stdio.h>
#include <ctype.h>

char ToUpperOrLower(char ch)
{
    if(isupper(ch))
    {
        return ch+32;
    }
    else if(islower(ch))
    {
        return ch-32;
    }
    else
    {
        return ch;
    }
}

int main()
{
    putchar(ToUpperOrLower('a'));
    putchar(ToUpperOrLower('z'));
    putchar(ToUpperOrLower('A'));
    putchar(ToUpperOrLower('Z'));
    putchar(ToUpperOrLower('@'));
    putchar(ToUpperOrLower('['));
    putchar(ToUpperOrLower(' '));
    putchar(ToUpperOrLower('{'));
    return 0;
}