Using If and Else Statements

[dancer13]

Hi all,

I am trying to work on a surprise for my boyfriend for Valentines. He is in computer programming so I want to write a little program scavenger hunt kinda thing for him.

To get started I want to have him enter his name. If it is his name it will allow him to continue and will say something like "hey you". If it is a different name it will say "invalid". I am having trouble getting it to work though.

Here is the code I have.

#include <stdio.h>
#include <string.h>


int main()
{
        char name[100];
        printf("Enter your name: ");
        fgets(name, 100, stdin);
        if (strcmp(name, "Brandon")==0 );
{       
        printf("hey youuu");
}
else
{
        printf("Invalid");
}
        return 0;
}

Please help!

[Salem]

> if (strcmp(name, "Brandon")==0 );
Remove the ; from the end of this line.

Also, be aware that name will have the \n still present from when fgets() wrote to the buffer.

See the FAQ for further info on fgets().

[dancer13]

That allows me to compile the program. But then when I type in Brandon after being asked to enter my name it says Invalid. How can I fix this?

(sorry really have no experience coding)

[stahta01]

FAQ > Get a line of text from the user/keyboard (C) - Cprogramming.com

[dancer13]

Okay so I understand that it is because there is a new line that my code isn't working right... but I'm still really confused as to how to fix it. Can anyone tell me what to add to my code specifically to fix this issue?

Thanks!

[algorism]

It's simple.

if (strcmp(name, "Brandon\n") == 0) {
    printf("Do me, baby!\n");
}
else {
    printf("Who are you? Do me anyway!\n");
}

Alternatively, you could remove the newline from the input string.

name[strcspn(name, "\n")] = 0;   // must include <string.h> for strcspn
if (strcmp(name, "Brandon") == 0)
...

The strcspn call essentially determines the position of the newline character (or the zero-terminator if there's no newline).

[dancer13]

Yay thank you I got that to work! (funny joke too) So now I want to make the code continue, so if the correct name is inputed it says the message and then asks the next question. How would I go about this...?

[algorism]

Maybe something like this. I removed the newline (so it's not needed in the comparison string) and also converted the input to lowercase for the comparison since you never know whether the user will upcase the first letter or write in all caps or whatever.

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

int main() {
    char name[100], *p;

    printf("Enter your name: ");
    fgets(name, 100, stdin);

    // Convert to lowercase and remove newline
    for (p = name; *p; p++)
        if (*p == '\n')
            *p = '\0';
        else
            *p = tolower(*p);

    if (strcmp(name, "brandon") != 0) {
        printf("I don't know you.\nGoodbye.\n");
        return 0; // end program
    }

    printf("Hey youuu\n");


    // continue code here ....


    return 0;
}