C++ Programming Code Examples
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While loop: two conditions
/* While loop: two conditions */
#include <iostream>
using namespace std;
int main(void)
{
int num;
char choice;
bool quit = false;
cout << "Enter a positive number: ";
cin >> num;
while (num <= 0 && quit == false)
{
cout << "Number must be positive; try again (Y/N): ";
cin >> choice;
if (choice != 'Y')
{
cout << "Enter number: ";
cin >> num;
}
else
quit = true;
}
if (quit == false)
cout << "The number you entered is " << num << " ";
else
cout << "You did not enter a positive number";
return 0;
}
#include is a way of including a standard or user-defined file in the program and is mostly written at the beginning of any C/C++ program. This directive is read by the preprocessor and orders it to insert the content of a user-defined or system header file into the following program. These files are mainly imported from an outside source into the current program. The process of importing such files that might be system-defined or user-defined is known as File Inclusion. This type of preprocessor directive tells the compiler to include a file in the source code program.
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In this control structure we have only one 'if' and one 'else', however we can have multiple 'else if' blocks. This is how it looks: If none of the 'condition is true' then these statements
