Question

In the code below in lesson2() i have used a password to enter the function but when i enter the function it does not takes in the passord and says incorrect password.By not taking in the password,i mean to say that i have used gets but its waiting for me to input a password.please dont tell me not to use gets!

#include<stdio.h>
#include<conio.h>
#include<string.h>
#include<dos.h>
int mistakes=0,mistakes_length,len;
char temp[100];
void lesson1(void);
void lesson2(void);
void result(void);
void main(void)
{
    int choice;
    clrscr();
    printf("Enter a lesson number to practise:1-10 \n");
    scanf("%d",&choice);
    switch(choice)
    {
        case 1:
        lesson1();
        result();
        break;
        case 2:
        lesson2();
        result();
        break;
        default:
        printf("You did not entered a valid choice program quitting..\n");
        exit(0);
    }
    getch();
}
void lesson1(void)
{
    int i;
    char str1[100]="testing the typing tutor if it works";
    mistakes_length=5;
    clrscr();
    gotoxy(25,2);
    puts("Welcome to lesson 1");
    puts(str1);
    len=strlen(str1);
    for(i=0;i<len;i++)
    {
        temp[i]=getche();
        if(strncmpi(&str1[i],&temp[i],1))//does not match
        {
            mistakes++;
            sound(100);
            delay(1000);
            nosound();

        }
    }
    getch();
}
void result(void)
{
    printf("Your statsistics are as under:\nYou performed this lesson with %d mistakes\n",mistakes);
    if(mistakes>=mistakes_length)
        {
                printf("\n Your typing is very bad");//allow anything to be typed with any mistake in lesson 1

        }
        if(mistakes>3&&mistakes<5)
        {
            printf("Bad!,You need to practise this excercise more\n");
        }
        if(mistakes>=1&&mistakes<=3)
        {
            printf("Good!you can still do better\n");
        }
        if(mistakes==0)
        {
            printf("Excellent!You are qualified for the next lesson\n");
            printf("The next lessons password is \n\t\t\t:12345");
        }
}

void lesson2(void)
{
    char password[]="12345",str2[]="My name is khan and i am not a criminal";
    int i;
    mistakes=0,mistakes_length=0,
    printf("Enter password:\n");
    gets(temp);
    if(strcmp(temp,password))
    {
        gotoxy(20,25);
        printf("Wrong Password,Program Quitting.\n");
        getch();
        exit(1);
    }
    gotoxy(25,25);
    printf("Password Accpted!");
    getch();
    clrscr();
    gotoxy(25,2);
    printf("Welcome to lesson 2\n");
    printf("Type the text shown below:\n");
    puts(str2);
    len=strlen(str2);
    for(i=0;i<len;i++)
    {
        temp[i]=getche();
        if(strncmp(&str2[i],&temp[i],1));
        {
            mistakes++;
        }

    }
    getch();
}

I think that it is the scanf and gets together making a problem!

Answer 1

Your problem is that prior to calling gets(), you have called scanf("%d",&choice); (in main()). The problem with this is that console input is line oriented. This means that although you are only waiting for a number to be entered the user has to enter a complete line ending in newline. The %d format specifier only consumes the digit characters leaving the rest of the line in the buffer to be used by the next console input call; which in this case is gets() which sees the newline in the buffer and returns an empty string without waiting for further input.

A solution:

scanf("%d",&choice);
while(getchar() != '\n' ) { /*no nothing*/}