Thread: quick question (please help

i am quite new to C, so my understanding of a few statements are unclear. first,

what is the meaning of selection, i know it has to do with programs being executed on basis of true of false, but a concrete defintion or example is still a bit unclear for me.

then, what could be a few good examples of if statement, if else, else statements

i did a few, dont know if i am correct, perhaps you could make some just to make it more clear.

if statement
# include<iostream.h>

void main()
{
int num1;

cout<<"Enter a number:";
cin>>num1;

if(num1>0)
cout<<"Number is greater then zero";
if(num1<0)
cout<<"Number is lesser than zero";
}

if else

#include <iostream.h> //Include the header file

void main() //Most important function
{
int age; //Variable declaration


cout<<"Enter your age please:"; //Prompt user for input
cin>>age; //Accept input

if(age>=18)
cout<<"Congrats! You are eligible to vote!";
else
cout<<"Sorry!You are not eligible!";

}


switch case

# include<iostream.h>

void main( )
{
int num1,num2,ch;

cout<<"\t\t\t MATH CALCULATOR\n\n\n";
cout<<"\t1. Add\n";
cout<<"\t2. Sub\n";
cout<<"\t3. Mul\n";
cout<<"\t4. Div\n";
cout<<"Enter 2 numbers:\n";
cin>>num1>>num2;
cout<<"Enter ur choice:";
cin>>ch;

switch(ch)
{
case 1:
cout<<num1+num2;
break;
case 2:
cout<<num1-num2;
break;

case 3:
cout<<num1*num2;
break;
case 4:
cout<<num1/num2;
break;
default:
cout<<"Wrong menu option!";
break;
}
}

any useful webpages that may be helpful

thanks for the help.

but dont you have a definition with a few short examples for selection

so far, my definition has been

"Function in C++ where the execution of the entire program branches out to a other different part within the program, depending if the value of the condition is TRUE or FALSE."

anything i should add, like an examples

Originally posted by geophyzzer
Okay, according to my favorite reference (Deitel & Deitel, "C++: How to Program") a selection is a generic term for a control structure that performs one of a series of tasks. Thus, the if, if-else, and switch structures are all selection structures. They imply that these are the only selection structures, but I don't think they come right out and say so.

Hope this helps

alright, that would make a good addition there. thanks.

what kind of program would be best for an example of a switch statement

so far i have the math calculator one only, but that is too long.

--------------------------------------

# include<iostream.h>

int main ( )
{
int num1,num2,ch;

cout<<"\t\t\t MATH CALCULATOR\n\n\n";
cout<<"\t1. Add\n";
cout<<"\t2. Sub\n";
cout<<"\t3. Mul\n";
cout<<"\t4. Div\n";
cout<<"Enter 2 numbers:\n";
cin>>num1>>num2;
cout<<"Enter ur choice:";
cin>>ch;

switch(ch)
{
case 1:
cout<<num1+num2;
break;
case 2:
cout<<num1-num2;
break;

case 3:
cout<<num1*num2;
break;
case 4:
cout<<num1/num2;
break;
default:
cout<<"Wrong menu option!";
break;
}
}

^-----------------------------

i am basically looking for a more brief program which is simpler and shorter.

This would be an example of a program using switch:

Code:

#include <iostream.h>
int main()
{
    int nVar;
    cout << "Pick a number (1/2)" << endl;
    cin >> nVar;
    switch(nVar)
    {
        case 1:
            cout << "You picked the number 1!" << endl;
            break;
        case 2:
            cout << "You picked the number 2!" << endl;
            break;
        default:
            cout << "Dumbass! Pick either 1 or 2!" << endl;
            break;
    }
    return 0;
}

Or you could make a guessing game
// Kavity

Originally posted by Kavity
This would be an example of a program using switch:

Code:

#include <iostream.h>
int main()
{
    int nVar;
    cout << "Pick a number (1/2)" << endl;
    cin >> nVar;
    switch(nVar)
    {
        case 1:
            cout << "You picked the number 1!" << endl;
            break;
        case 2:
            cout << "You picked the number 2!" << endl;
            break;
        default:
            cout << "Dumbass! Pick either 1 or 2!" << endl;
            break;
    }
    return 0;
}

Or you could make a guessing game
// Kavity

thanks a lot mate. but the dumbass part isnt something you want to have when presenting this to a group of 40 year olds...

so do you know anything about hacking? does it involve C++

any useful webpages that may be helpful

There are some good tutorials on this website, check them out