Thread: Why my 'count the characters' program doesn't work?

I was trying to make a c program to count the number of characters entered, and here is the code:

Code:

#include<stdio.h>
#include<stdlib.h>
int main()


{
int i=0;
while(getchar()!= EOF)
    ++i;
printf("%d\n", i);
}

Well this doesn't work. After entering the string there is no value printed. It also doesn't work if I declare char c and use scanf.

But the following code works :

Code:

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


int main()
{
int cl=0,i;
char str[20];
gets(str);
for(i=0; str[i]!= NULL ; i++)
{
    cl = cl +1;
}
printf("%d", cl);

}

Why I don't know. Btw I am using codeblocks IDE with gcc compiler.

You're asking it to count characters until EOF, which is not end-of-line.
So you need to signal the "end-of-file" from the keyboard, which is ctrl-d on *nix, ctrl-z on Windows. It may need to be entered at the beginning of a line (or perhaps entered twice).

To count to the end of a line, compare to '\n' instead.
In the following, signal eof to quit.

Code:

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

int main() {
    int i = 0, c = 0;
    while (c != EOF) {
        i = 0;
        while ((c = getchar()) != EOF && c != '\n')
            ++i;
        if (c != EOF)
            printf("%d\n", i);
    }
    return 0;
}

Well I tried signalling eof by pressing ctrl-z but it just prints ^z on the console. :\

Originally Posted by Noobpati

Well I tried signalling eof by pressing ctrl-z but it just prints ^z on the console. :\

So I assume you're on Windows. Did you press ctrl-z at the beginning of a line as I said?

To count to the end of a line, compare to '\n' instead.

I see, but if I use '\n' to signal exit how can I write a program to count the number of lines.
Also it tried entering ctrlz at the start and at the end of line and it prints zero in that case but if I write ctrlz after pressing enter that is , on the new-line then it prints value greater than the number of characters given. I guess it also counts ^z.

Originally Posted by Noobpati

I see, but if I use '\n' to signal exit how can I write a program to count the number of lines.

I didn't say to use '\n' to signal exit. Try the program that I posted. For me (on linux) it prints the count of the number of characters in the line just entered, and when I press ctrl-d on a new line it simply exits.

Also it tried entering ctrlz at the start and at the end of line and it prints zero in that case but if I write ctrlz after pressing enter that is , on the new-line then it prints value greater than the number of characters given. I guess it also counts ^z.

Well I don't use windows, so I can't help you there.