You will want to do a few things here. First, replace gets with fgets. Then, you're going to want to use strcmp from string.h to compare the input with the desired result. The code listed below has been updated with a working example with the previously mentioned recommendations. This isn't perfect and there are other ways to accomplish the same task. Explore other options that are available when you have a chance and see if you can improve on this example.

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

int main()
{ 
    char name[10], 
    pasword[10]; 

    printf("enter you user name :"); 

    // Use fgets as gets is insecure and can easily lead to buffer overflow exploits
    fgets(name, sizeof(char) * sizeof(name), stdin);

    // Remove \n from fgets stdin read with null character so as to not have to include
    // in strcmp later.
    name[strlen(name) - 1] = '\0';

    printf("enter your pasword : "); 
    fgets(pasword, sizeof(char) * sizeof(pasword), stdin);

    printf("your name : %s \n your password : %s \n", name, pasword);

    // If strcmp result > 0 || < 0 it's not a match
    if (strcmp(name, "youcef") != 0) 
    { 
        printf("name undefined\n"); 
    } 
    else 
    { 
        printf("finde name"); 
    }
}

Dear, Yusuf You can't use if statement to compare two strings, but you can use strcmp() function which means string compare The behavior of strcmp function is: If (string1 < string2)? Then: return a negative value. If (string1 > string2)? Then: return a positive value.

If(string1 == string2)? Then: return (0).

So, you can modify this statment to: if(strcmp(name,"Yousef") != 0) printf("name undefined\n");

else printf("find name");

But, In this case there is one logic problem that (strcmp) function don't ignore the letter case. For example: If you input name : yousef

The first letter here (y) is small, but in the comparing statement above is capital, So the result will be "name undefined", but in fact "yousef" = "Yousef".

To solve this problem you should use stracasecmp() function. This function ignore the letter case while comparing. The code will be: if(strcasecmp(name,"Yousef") != 0) printf("name undefined\n");

else printf("find name");

Attention: Include string libreary after using these functions to skip any problem may be found.

include

may Allah bless you ^_^