This program uses nested while loops to calculate various factorials. The workings for each factorial are displayed on the screen, along with the answer in bold:
Select and copy the C++ source-code at the bottom of this post.
Paste into a text editor, such as Nano or Geany.
Then save the new file, ending in .cpp
I used factorial.cpp
To compile from the command-line:
g++ -o factorial.cpp factorial
To run from the command-line:
./factorial
Here's the code:
#include <iostream> // Program will be displaying some text on the screen
using namespace std; // Will be using standard identifiers cout and endl
int main()
{
const string BOLD = "\e[1m";
const string NORMAL = "\e[0m";
cout << "FACTORIAL PROGRAM" << endl;
cout << "=================" << endl;
int factorialToCalculate = 1;
// Outer while loop - controls WHICH factorial is being calculated
while ( factorialToCalculate <= 10 )
{
cout << "Factorial of " << BOLD << factorialToCalculate << NORMAL << " is ";
cout << factorialToCalculate; // Working starts with the number itself
int num = factorialToCalculate;
unsigned long long resultSoFar = num; // Builds up the product of all values
// Inner while loop - calculates an individual factorial
while ( num > 1 )
{
num--;
cout << " x " << num;
resultSoFar *= num;
} // end of inner while loop
// Display the final result for this factorial
cout << " = ";
cout << BOLD << resultSoFar << NORMAL << endl;
factorialToCalculate++;
} // End of outer while loop
return 0;
}
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