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A little help here please!!!

pankar94 (3)
Hello guys.I have made a program that asks the user to type his/her name and password.It will continue only if username is "user" and password is "pass".Otherwise it will ask again for the correct details.After he/she login he/she will have a menu and some submenus to choose.My problem is that all the code is in main.There are no functions.Should I create some in order to simplify the main?

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#include<iostream>

using namespace std;
main()
{

int pick,pick2,pick3;
string name;
string pass,pick4;




cout<<"Hello user.Please login to your account\n";
start1:
cout<<"Type your username\n";
cin>>name;
cout<<"Now your password\n";
cin>>pass;

do {


if ((name=="user")&&(pass=="pass"))
{
cout<<"Welcome "<<name<<"\n";
}

else {
cout<<"Wrong details\n";
goto start1;
}

}
while (name!="user" and pass!="pass");




cout<<"My name is IF4T and I am your personal computer.\nNow you have some options to choose\n";
start3:
cout<<"1. My Documents\n2. My Account\n3. Media Center\n4.Language\n5.Quit\n";
cin>>pick;

do switch (pick){

	case 1: cout<<"There are no documents.\n";
		cout<<"Do you want to go back?[Yes/No]\n";
	start4:
	cin>>pick4;
	if (pick4=="Yes"||"yes"||"YES"){
		goto start3;
	}
else if (pick4=="No"||"NO"||"no"){
	goto end1;
}
else {
cout<<"I dont understand.Please select Yes or No]\n";
goto start4;
}break;
	case 2: cout<<"No pictures\n";
		cout<<"Do you want to go back?[Yes/No]\n";
	start5:
	cin>>pick4;
	if (pick4=="Yes"||"yes"||"YES"){
		goto start3;
	}
else if (pick4=="No"||"NO"||"no"){
	goto end1;
}
else {
cout<<"I dont understand.Please select Yes or No]\n";
goto start5;
}break;
	case 3: cout<<"1. Video\n2. Music\n3. Pictures\n";
start:                                 

	cin>>pick2;
	
	if (pick2==1)
{
		cout<<"No video files\n";
}
		
		else if (pick2==2){
			cout<<"No Music files\n";
			
		}
		else if (pick2==3){
			cout<<"No pictures\n";
		}
		
		
	else
	{cout<<"Please select again.\n";
goto start;
	}
	cout<<"Do you want to go back?[Yes/No]\n";
	start6:
	cin>>pick4;
	if (pick4=="Yes"||"yes"||"YES"){
		goto start3;
	}
else if (pick4=="No"||"NO"||"no"){
goto end1;}
else {
cout<<"I dont understand.Please select Yes or No]\n";
goto start6;
}
	break;
		
	case 4: cout<<"1. English\n2. German\n3. Frence\n"; 
	start2:	
	cin>>pick3;
	
	if (pick3==1){
		cout<<"English\n";
}
		
		else if (pick3==2){
			cout<<"German\n";
			
		}
		else if (pick2==3){
			cout<<"Frence\n";
		}
	else
	{cout<<"Please select again.\n";
goto start2;
	}	cout<<"Do you want to go back?[Yes/No]\n";
	start7:
	cin>>pick4;
	if (pick4=="Yes"||"yes"||"YES"){
		goto start3;
	}
else if (pick4=="No"||"NO"||"no"){
	goto end1;
}
else {
cout<<"I dont understand.Please select Yes or No]\n";
goto start7;
}break;
	case 5:cout<<"quiting...\n";exit;break;
	default:cout<<"Invalid choice"<<endl;}
	while (!(pick>=1 and pick<=5));
end1:
system ("pause");

}
TheIdeasMan (6817)
Hi,

Yes you should definitely use functions. There is a convention that functions should be less than 40 LOC, including main().

main() returns an int by the way, so it should be int main() {

While you are at it, you could get rid of the goto , use loops instead. This is not a hard and fast rule for everyone, but it is for beginners :+)

Also, this :

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	if (pick4=="Yes"||"yes"||"YES"){
		goto start3;
	}
else if (pick4=="No"||"NO"||"no"){
	goto end1;
}


If you restrict the input to y or n, the logic is much simpler. One can use toupper or tolower to get a consistent case.

If you were to continue using this, then it would have to look like this:

if (pick4=="Yes" || pick4 == "yes" || pick4== "YES")

But you haven't accounted for every combination, so that is why I recommend using a single char as input.

Good Luck ! :+)


Edit:

I try to avoid do loops - it often means that end conditions are tested twice, and they can be error prone. Were you aware that all 3 types of loops can be converted to one of the other types. So I prefer while loops when the exact number of iterations isn't known (some condition instead), and for loops when the number of iterations is known.

Just because a loop must be executed once, doesn't necessarily mean that it has to be a do loop.
Last edited on
pankar94 (3)
Thanks for your reply.I will try to fix it.
dhayden (5798)
When validating input, I often find it easiest to break out of the loop in the middle. For example:
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    cout<<"Hello user.Please login to your account\n";
    while (true) {
	cout<<"Type your username\n";
	cin>>name;
	cout<<"Now your password\n";
	cin>>pass;

	if ((name=="user")&&(pass=="pass")) {
	    break;
	} else {
	    cout<<"Wrong details\n";
	}
    }

    cout<<"Welcome "<<name<<"\n";

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