Newbie question: Kernighan-Ritchie C book- problem

**plutonas** · 06-29-2005

Hi this is my first post here...
I am learning C right now(through the book on the Title), so my knowledge about the language is very small...

So, in the first chapter of the book there is a programm about tables, which counts how many times every digit, every "white" space(" ","\n" etc) and other "letters" appear in a text.

So I wrote down the code exactly as in the book:

Code:

#include<stdio.h>
main()
{
int c,i,nwhite,nother;
int ndigit[ 10];

nwhite = nother=0;
for (i=0 ; i<10 ; ++i)
        ndigit[i]=0;
while((getchar()) !=EOF)
                if (c>='0' && c<='9')
                 ++ndigit[c-'0'];

                else
                        if (c==' ' || c=='\n' || c=='\t')
                 ++nwhite;

                        else
                 ++nother;

                  printf("Ta psifia einai");
                for( i = 0 ; i < 10 ; ++i)
                  printf("%d",ndigit[i]);
                  printf(",ta leyka diastimata einai %d, kai oi alloi xaraktires %d", nwhite, nother);
                  printf(".Sas eyxaristoume pou mas kalesate.\n");

                  }

According to the book when I run the programm, I should take something like that:
digits 9300000001
white spaces 124
other 330
----------------
Now my problem:
I get always digits: 0000000000
white spaces 0
and other: the number of the characters in the text...
no matter what text I use...
------------------
I would be very glad if someone could find the error...
Thanks a lot,
plutonas

**mitakeet** · 06-29-2005

You ain't puttin nuthin in c! Your while loop is also wrong and you are not initializing your variables. Try this:

Code:

#include<stdio.h>

int main() {
    int c,i,nwhite=0,nother=0;
    int ndigit[ 10];

    nwhite = nother=0;
    for (i=0 ; i<10 ; ++i)
        ndigit[i]=0;
    while((c = getc(stdin))!=EOF){
        if (c>='0' && c<='9')
            ++ndigit[c-'0'];
        else if (c==' ' || c=='\n' || c=='\t')
            ++nwhite;
        else
            ++nother;
    }
    printf("Ta psifia einai");
    for( i = 0 ; i < 10 ; ++i)
        printf("%d",ndigit[i]);
    printf(",ta leyka diastimata einai %d, kai oi alloi xaraktires %d", nwhite, nother);
    printf(".Sas eyxaristoume pou mas kalesate.\n");
    return 0;
}

**kermit** · 06-29-2005

With all due respect to Mitakeet's post (he correctly pointed out your problems), I would add that looking in my copy of K&R2, it seems that your code should look like the following:

Code:

#include<stdio.h>
main()
{
int c,i,nwhite,nother;
int ndigit[ 10];

nwhite = nother=0;
for (i=0 ; i<10 ; ++i)
        ndigit[i]=0;
while((c = getchar()) !=EOF)
                if (c>='0' && c<='9')
                 ++ndigit[c-'0'];

                else
                        if (c==' ' || c=='\n' || c=='\t')
                 ++nwhite;

                        else
                 ++nother;

                  printf("Ta psifia einai");
                for( i = 0 ; i < 10 ; ++i)
                  printf(" %d",ndigit[i]);
                  printf(", ta leyka diastimata einai %d, kai oi alloi xaraktires %d", nwhite, nother);
                  printf(".Sas eyxaristoume pou mas kalesate.\n");

                  }

edit:: Dave, you type too fast!

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