There are quite a lot of mistakes in your program (still!). So instead of pointing out each and every of them, I just whipped up my own code and have offered explanations through comments.

c Syntax (Toggle Plain Text)

#include <stdio.h>
#include <conio.h>
#include <string.h>
 
 
int main()
{
 
    char *loginID[] = {"user1", "user2", "user3"};
    char *passwords[] = {"pass1", "pass2", "pass3"};
    char login[6];
    char pass[6], temp;
    int i, loginNumber;
    printf("Enter the login id\n");
    fgets(login,6,stdin); // Use fgets instead of gets or scanf(%s)
    for(i=0; i < 3; i++) // Need to see if the entered login ID is any one of the three login IDs
    {
        if(!strcmpi(loginID[i],login)) //strcmpi() ignores case
            break;
    }
    if(i == 3) //If the login ID didn't match in any of the three cases
    {
        printf("Invalid login id\n");
        getchar();
        exit(0);
    }
 
    loginNumber = i; //need to store the subscript of the login ID
    login[6] = '\0'; //NULL terminated string
    printf("Enter the password\n");
    while((temp = getc(stdin)) != '\n') // flush the input. Google it! Don't use fflush(stdin)
    ;
 
    for(i=0; (temp = getch()) != '\r'; i++) //Loop executes till 'enter' is pressed
    {
        printf("*");
        pass[i] = temp;// store character in pass
    }
    pass[6] = '\0';
    if(!strcmp(passwords[loginNumber], pass))//compare with the appropriate loginID. Use strcmp
    {
        printf("\nAccess granted!\n");
        getchar();
        exit(0);
    }
    else
    {
        printf("\nAccess denied!\n");
        getchar();
        exit(0);
    }
    return 0;
}

#include <stdio.h> #include <conio.h> #include <string.h> int main() { char *loginID[] = {"user1", "user2", "user3"}; char *passwords[] = {"pass1", "pass2", "pass3"}; char login[6]; char pass[6], temp; int i, loginNumber; printf("Enter the login id\n"); fgets(login,6,stdin); // Use fgets instead of gets or scanf(%s) for(i=0; i < 3; i++) // Need to see if the entered login ID is any one of the three login IDs { if(!strcmpi(loginID[i],login)) //strcmpi() ignores case break; } if(i == 3) //If the login ID didn't match in any of the three cases { printf("Invalid login id\n"); getchar(); exit(0); } loginNumber = i; //need to store the subscript of the login ID login[6] = '\0'; //NULL terminated string printf("Enter the password\n"); while((temp = getc(stdin)) != '\n') // flush the input. Google it! Don't use fflush(stdin) ; for(i=0; (temp = getch()) != '\r'; i++) //Loop executes till 'enter' is pressed { printf("*"); pass[i] = temp;// store character in pass } pass[6] = '\0'; if(!strcmp(passwords[loginNumber], pass))//compare with the appropriate loginID. Use strcmp { printf("\nAccess granted!\n"); getchar(); exit(0); } else { printf("\nAccess denied!\n"); getchar(); exit(0); } return 0; }

The above code is still a li'l crappy since it uses non-portable getch(). I couldn't figure out any other way of getting the password without it being echoed to the screen. Maybe someone else will show a way.

The reason for not using scanf(or gets) can be found here. You can read other related articles too over there.