First C++ Attempt/Total Noob

[Ilhan]

Hey there, guys. Very first time doing any type of coding, literally started watching videos yesterday. So this is a very basic problem.. I've used google to try and find the answer to my woes but I can't find anything. The problem is with the code below - Instead of going to my 'for' loop, it immediatly bipasses it and head to the "You've won!"

Guessing it's something simple and quick. Thanks.

#include "stdafx.h"

#include <iostream>

using namespace std;

int main()
{
    int secretnumber = 76;
	int playerguess;
	int lives = 7;

	cout << "--------!Guess my number!-------- \n \n";
	cout << "!My number is between 0 and 100! \n-------------------------------- \n \n";
	
	for ( ; lives = 0 ; )
	{
		cout << "What do you think it is.... : ";

		cin >> playerguess;


		if (playerguess == secretnumber)
		{
			cout << "You got it! \n";
			cout << "You got it! \n";
			cout << "You got it! \n";
			cout << "You got it! \n";
			break;
		}
		else
		{
			cout << "\n";
			cout << "You didn't get it! \n \n";

			if (playerguess > secretnumber)
			{
				cout << "Lower! \n";
				lives -= 1;
				cout << "You have : " << lives << "\n";
			}
			else
				if (playerguess < secretnumber)
				{
					cout << "Higher! \n";
					lives -= 1;
					cout << "You have : " << lives << "\n";
				}
				else
					cout << "!This can't be possible! \n";
		}
	}
	
	if (lives = 0)
		cout << "You've lost! You ran out of lives!";
	else
	{
		cout << "You've Won! \n";
		cout << "----------- \n";
		cout << "!Well done! \n";
	}

	char f;
	cin >> f;
	return 0;
}

[Lynx876]

Use a for-loop, something like:

for( lives = 5; lives > 0; lives-- )
{
    /* code */
}

EDIT:
http://www.cplusplus.com/doc/tutorial/control/
Scroll about half way down.

[Moschops]

for ( ; lives = 0 ; )

I expect you meant

for ( ; lives == 0 ; )

Likewise elsewhere.

[LB]

As for an explanation of why it bypassed the for loop, here are the elements that cause the problem:

int a;
int b = (a = 7); //a and b are both 7 now, because (a = 7) returns a, thus b = a;

if(0){} //this condition is the same as if(false)
if(1){}
if(2){} //these three are the same as if(!false) or if(true)
if(3){}

for(; lives = 0;){} //because "lives = 0" returns lives, and lives is 0, the condition is false
//thus, the loop doesn't even run once. 

[Ilhan]

@Lynx876 Amended. Thanks.

@Moschops Should have noticed that, yeah. Thanks.

@L B Don't understand why that's a problem. Probably don't know one of the basic rules I suppose..? Surely it's not a problem to tell the For loop to stop if lives is 0 or False?
Possible for you to give a example of a way to fix this?

[LB]

The problem is that you used "=" for assignment instead of "==" for equality check, as Moschops pointed out. I just explained how that affected it. ;)

[Lynx876]

LB is basically saying what Moschops said.

You're using assignment( = ) operators, instead of equality( == ) operators.

Anything other than 0, within an if-statement will be true, only if( 0 ) will be false.
Which is why L B wrote:

if(0){} //this condition is the same as if(false)
if(1){}
if(2){} //these three are the same as if(!false) or if(true)
if(3){}

Check line 54 of your code, you're assigning instead of checking for equality.

EDIT:
What he said ^^^^^ lol!

[Ilhan]

Ha. Ugh fuck. I hate feeling like a total noob.

I *hope* (almost certain) I have just understood what you've said. I've changed the coding to this, no positive results. Apologies.

#include "stdafx.h"

#include <iostream>

using namespace std;

int main()
{
    int secretnumber = 76;
	int playerguess;
	int lives = 7;

	cout << "--------!Guess my number!-------- \n \n";
	cout << "!My number is between 0 and 100! \n-------------------------------- \n \n";
	
	for ( ; lives == 0 ; lives-- )
	{
		cout << "What do you think it is.... : ";

		cin >> playerguess;


		if (playerguess == secretnumber)
		{
			cout << "You got it! \n";
			cout << "You got it! \n";
			cout << "You got it! \n";
			cout << "You got it! \n";
			break;
		}
		else
		{
			cout << "\n";
			cout << "You didn't get it! \n \n";

			if (playerguess > secretnumber)
			{
				cout << "Lower! \n";
				cout << "You have : " << lives << "\n";
			}
			else
				if (playerguess < secretnumber)
				{
					cout << "Higher! \n";
					cout << "You have : " << lives << "\n";
				}
				else
					cout << "!This can't be possible! \n";
		}
	}
	
	if (lives == 0)
		cout << "You've lost! You ran out of lives!";
	else
	{
		cout << "You've Won! \n";
		cout << "----------- \n";
		cout << "!Well done! \n";
	}

	char f;
	cin >> f;
	return 0;
}

[Lynx876]

for( ; lives > 0; lives-- )

for( ; while lives are greater than 0( run statements within loop); take 1 from lives )

[WhiteWind]

You need to change your for loop to what Lynx suggestion in the second post:

for( lives = 5; lives > 0; lives-- )
{
    /* code */
}

which:
- Sets lives to 5 (you want 7, so put 7)
- Loops over and over while lives is still above 0
- Reduces lives by 1 every loop

Currently your for loop runs while lives is 0, but you start with 7, so that's never.

[Ilhan]

@Lynx876

Brilliant. Perfecto. Thanks alot, I had it in my head that it exited the loop on the requirements of that middle section rather than staying in. Vastly appreciated.

[Lynx876]

No problem. From the link I gave above;

Its format is:

for (initialization; condition; increase) statement;

[LB]

Yes, but it is often unclear from just that line whther the loop goes until condition is true or until it is false. ;)