If else statements

This is a discussion on If else statements within the C++ Programming forums, part of the General Programming Boards category; I am currently coding a small program to comment on your age, and I am having problems with if else ...

  1. #1
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    If else statements

    I am currently coding a small program to comment on your age, and I am having problems with if else statements.

    Code:
    #include <iostream>
    
    using namespace std;
    
    int main()
    {
     int age;
    
     cout<<"Please enter your age: \n";
     cin>> age;
     cin.ignore();
    
     if ( age <= 1 ) {
        cout<<"You are a baby!\n";
        }
    
     else if ( age <= 3 and > 1 ) {
          cout<<"You are a toddler.\n";
          }
    
     else else if ( age <= 12 and > 3 ) {
          cout<<"You are a child.\n";
          }
    
     else else else if ( age < 18 and > 12 ) {
          cout<<"You are a teenager.\n";
          }
    
     else else else else if ( age >= 18 and < 45 ) {
          cout<<"You are an adult.\n";
          }
    
     else else else else else if ( age >= 45 and <= 55) {
          cout<<"You are middle aged.\n";
          }
    
     else {
          cout<<"You are old!\n";
          {
    
     cin.get();
    }
    As you can see, i add and extra else everytime. This doesn't work, so i was wondering what i need to do to make this work.

  2. #2
    CSharpener vart's Avatar
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    not "and"
    age >1 && age <= 3

    and don't use several else else else... just one is possible

    if ..
    else if ...
    else if ...
    else if ...
    ...
    else ...
    The first 90% of a project takes 90% of the time,
    the last 10% takes the other 90% of the time.

  3. #3
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    is that all id need to change?

  4. #4
    CSharpener vart's Avatar
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    Quote Originally Posted by Timbo8
    is that all id need to change?
    You should also check that the age is >= 0 - otherwise discard the user's input
    The first 90% of a project takes 90% of the time,
    the last 10% takes the other 90% of the time.

  5. #5
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    you would need a loop to do that, wouldnt you?

  6. #6
    CSharpener vart's Avatar
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    you can start with printing out the error message asking to enter the age in the specified range and exit...

    When the program will work as desired you can add the loop to process till the correct value is entered (or opposite, till the first negative value is entered)...
    The first 90% of a project takes 90% of the time,
    the last 10% takes the other 90% of the time.

  7. #7
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    >> not "and"

    Actually, "and" is legal. However, it would probably be wise to use "&&" instead so that programmers who are not familiar with that information are not confused by the code.

  8. #8
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    Due to the nature of the if-else structure, you don't actually need to check
    "else If age is between 1 and 3" ...
    "else if age is between 3 and 12"...
    "else if age is between 12 and 18"... etc

    the following would work in exactly the same way, and looks a bit neater:

    "if age is less than 1"...
    "else if age is less than 3"...
    "else if age is less than 12"...
    "else if age is less than 18"...

    The reason for this - All the conditions are evaluated in order. "else..." does not get executed when "if" yeilds true, so, the entire if/else block terminates as soon as one of the conditions is matched.

  9. #9
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    so they are done in order? But also, how would i check to see if the entered age is below 0, and dispose of it if it is?

  10. #10
    The larch
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    Put if age < 0 as the first in the if-else chain

  11. #11
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    and then if it is less than 0 go back to where it asks for the age?

  12. #12
    Its hard... But im here swgh's Avatar
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    Either that or print an error message then exit the program. But if you are going with the first choice i many be better to use a loop. Keep asking as lond as the expression is true and terminmate the loop at a sentinal value entry, usually -1
    I'm just trying to be a better person - My Name Is Earl

  13. #13
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    'and" is not recognised by the compiler. you use &&(ampersand) or ||(or) .. && means the word and in english and || is or.. so to make it possible use || because && is only limited it the 1st condition is true then the second it false it is false...

  14. #14
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    joseph that information is solely dependent on your compiler, as my compiler recognizes the words and, or, not, but also uses &&, ||, !. Although I would reccomend using the symbols not the words 1) so other compilers are sure to be able to use it, 2) it isnt as confusing

  15. #15
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    Actually, as I already mentioned "and" is legal and all standards compliant compilers must recognize it as an alternate keyword for &&.

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