Thread: Else if problem (noob)

You declared user_age_2 to be a string.

Hey! Noob here as well.

Your problem seems to lie at line 32. You put the "else" statement before your "else if" statement, this is a common newbie mistake so don't fret. Before continuing on, I would highly recommend you change your variable type from "string" to "int". So no that we've taken care of those two major road blocks, my next advice and really the only option here, is to throw out the "else" statement" and just add in another "else if" statement. I've rewritten your code below,

Code:

#include <iostream>
using namespace std;


int User_Age_1, User_Age_2;


int main()
{
   cout << "User 1- Enter your age: ";
   cin >> User_Age_1;
   cout << "User 2- Enter your age: ";
   cin >> User_Age_2;


   if (User_Age_1 < User_Age_2)
   {
       cout << "User 2 is older than User 1.";
   }
   else if (User_Age_1 > User_Age_2)
   {
       cout << "User 1 is older than User 2.";
   }
   else if (User_Age_1 > 100 && User_Age_2 > 100)
   {
       cout << "Both users are older than 100.";
   }
   else if (User_Age_1 == User_Age_2)
   {
       cout << "Both users are the same age.";
   }
   return 0;
}

Hope this helps!

Originally Posted by C_Plus_Plus_96

Hope this helps!

not as much as you'd think. you gave the OP a full solution. this is against the rules. how is anyone supposed to learn if you just give them the answers?

I think you could have explained the necessary course of action without providing the full code of a solution. in most cases, this is preferred over simply handing out code.

I still think the last else if should be an else.
Global variables should be avoided, too. There is no reason for the variables to be local in this example, either, so I would make them local.
Also remember that while you can order strings (i.e. some_string < some_other_string), it is not the same as comparing two integers. Case in point: You may find that "100" < "2" hold for strings, but it definitely does not hold for integers!

Originally Posted by Elysia

There is no reason for the variables to be local in this example, either, so I would make them local.

just to help avoid confusion, I'm going to go out on a limb here, and assume that you meant:

There is no reason for the variables to be global in this example, either, so I would make them local.

italics to show the change.

Except quotes are all italics, so it is kind of hard to know where the emphasis is, so I am going to guess that you meant...

There is no reason for the variables to be global in this example, either, so I would make them local.

...and if so, you are right.

Originally Posted by Elysia

Except quotes are all italics, so it is kind of hard to know where the emphasis is, so I am going to guess that you meant....

indeed. silly forum, doing what I said, instead of what I meant.

Originally Posted by russiancircles

I actually did try switching places between the else if and the else-command, didn't seem to work, maybe it was because i used string instead of int? Anyway, thank you for your answer!

Your final statement of an if else-if block of code should always be just else.

Such as:

Code:

if(something)
{
	do something
}
else if(something different)
{
	do something else
}
else
{
	do something else
}

Originally Posted by russiancircles

I actually did try switching places between the else if and the else-command, didn't seem to work, maybe it was because i used string instead of int?

It didn't work because it is syntactically incorrect. Every else must have a matching if, so this:

Code:

if (user_age_1 < user_age_2)
{
    cout << "user number 2 is older than user number 1" << "\n";
}
else
{
    cout << "user number 1 is older than user number 2" << "\n";
}
else if (user_age_1 > 100 && user_age_2 > 100)
{
    cout << "both users are over a 100 years old" << "\n";
}

is equivalent to:

Code:

if (user_age_1 < user_age_2)
{
    cout << "user number 2 is older than user number 1" << "\n";
}
else
{
    cout << "user number 1 is older than user number 2" << "\n";
}
else
{
    if (user_age_1 > 100 && user_age_2 > 100)
    {
        cout << "both users are over a 100 years old" << "\n";
    }
}

Obviously, the second else does not have a matching if. On the other hand this:

Code:

if (User_Age_1 < User_Age_2)
{
    cout << "User 2 is older than User 1.";
}
else if (User_Age_1 > User_Age_2)
{
    cout << "User 1 is older than User 2.";
}
else if (User_Age_1 > 100 && User_Age_2 > 100)
{
    cout << "Both users are older than 100.";
}
else if (User_Age_1 == User_Age_2)
{
    cout << "Both users are the same age.";
}

is equivalent to:

Code:

if (User_Age_1 < User_Age_2)
{
   cout << "User 2 is older than User 1.";
}
else
{
    if (User_Age_1 > User_Age_2)
    {
        cout << "User 1 is older than User 2.";
    }
    else
    {
        if (User_Age_1 > 100 && User_Age_2 > 100)
        {
            cout << "Both users are older than 100.";
        }
        else
        {
            if (User_Age_1 == User_Age_2)
            {
                cout << "Both users are the same age.";
            }
        }
    }
}

Clearly, every else has a matching if. There is an if with no else, but that is not a problem.

Originally Posted by Ewiv

Your final statement of an if else-if block of code should always be just else.

That's not accurate, as C_Plus_Plus_96 demonstrated in post #3 and as I have elaborated on in this post.