Stuck in comparing "++X" with another string in C

Question

I am trying to take a string as input and if it's equal to X++ or ++X, I would like to count it. for this purpose, I have written value code. Though it's working correctly for X++, for X-- it's not working. How can I solve the problem?

#include<stdio.h>
#include<string.h>
int main() {
    int n,count=0;
    char c[5];
    scanf("%d",&n);
    for(int i=0;i<n;i++){
        scanf("%s",c);
        if(strcmp(c,"X++")==1 || strcmp(c,"++X")==1) count++;
        else count--;
    }
    printf("%d",count);
    return 0;
}

It shouldn't be working correctly for either of them. What makes you think it is? — Barmar, Jul 10 '21 at 07:58
Read closely the documentation of `strcmp`, especially what values it returns. Is it stated explicitely that `strcmp` can return `1`? — Jabberwocky, Jul 10 '21 at 08:03

score 2 · Answer 1 · edited Jul 10 '21 at 13:23

2

You might want to change strcmp(c,"X++")==1 to strcmp(c,"X++")==0, and strcmp(c,"++X")==1 to strcmp(c,"++X")==0. strcmp() will return 0 if its arguments are equal, not 1. You can read more about strcmp() here.

edited Jul 10 '21 at 13:23

Eric Postpischil

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answered Jul 10 '21 at 07:49

JASLP doesn't support the IES

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Oops. i just thought it as binary meaning. Thanks. but when i run the code why it was worked for X++? – Md Nasir Ahmed Jul 10 '21 at 08:04
@MdNasirAhmed As Barmar said in the comment, it'll not work for either of those. Can you give an example of what you mean by "why it worked for X++"? As a side note, you can always check the return value of `strcmp()` to understand what your program actually does. – JASLP doesn't support the IES Jul 10 '21 at 08:14
@LonelyProgrammer Sorry, I don't know, why my ide was showing count=1 when i entered X++. But now I checked on a online compiler and also checked the return value of the condition and i found you both (you and @Barma) was correct. Thanks to you all. – Md Nasir Ahmed Jul 10 '21 at 08:29
@EricPostpischil what do you mean by "only one of its arguments is equal"? – JASLP doesn't support the IES Jul 10 '21 at 12:51
@EricPostpischil My appologies, English is not my native language. I'll edit it now. – JASLP doesn't support the IES Jul 10 '21 at 13:06
@JustASimpleLonelyProgrammer: No worries, it is just a funny thing, not an error. – Eric Postpischil Jul 10 '21 at 13:06
@EricPostpischil I edited it. I hope it makes more sense now. Thanks for pointing it out. – JASLP doesn't support the IES Jul 10 '21 at 13:09

Stuck in comparing "++X" with another string in C

1 Answers1