20141223_KUAS_VisualC++_Exam10

/**************************************/
/** 20141223 Exam 10                 **/
/** Maker  : Yan                     **/
/** E-Mail : [email protected] **/
/** Date   : 2014/12/23 am.11:32     **/
/**************************************/

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

int main(int argc, char const *argv[])
{
    FILE *fptrIn = fopen("Data.txt", "r");

    while(!feof(fptrIn))
    {
        char temp = NULL;
        temp = fgetc(fptrIn);
        if(islower(temp))
            putchar(toupper(temp));
        else if(isupper(temp))
            putchar(tolower(temp));
        else if(isdigit(temp))
            putchar(temp);
    }
    fclose(fptrIn);
    return 0;
}