Plandrome Checker

Hi. I remember during first year of university when I was studying introduction to computer science course. It was a nice course where our professor taught us the basics of C++. The real fun was in solving problems related to numbers. There were few types of numbers that I was not aware of such as: palindromic numbers, perfect numbers. We were assigned to create simple looping programs where the user enters a number and the program has to check wether the number satisfies the conditions related to its type. Here I will share my code that checks wether an entered number is palindromic number or not. First, let's check the meaning of Palindrome in dictionary, and here what it says:

palindrome |ˈpalɪndrəʊm|

noun

a word, phrase, or sequence that reads the same backwards as forwards, e.g. madam or nurses run.

DERIVATIVES

palindromic |-ˈdrɒmɪk| adjective,

palindromist noun

ORIGIN early 17th cent.: from Greek palindromos ‘running back again’, from palin ‘again’ + drom- (from dramein ‘to run’).

The following program was coded in Visual C++, .NET Framework 3.5 using Visual Studio 2010. If you are looking for a code in a different language, at least you can understand the concept of this code that I will explain directly after the following code:

	// Palidnrome_Checker.cpp : Defines the entry point for the console application.
	//
	#include <iostream>
	using namespace std;
	int main(int argc, char* argv[])
	{
	long number; //to store input number
	long reversed_number; //to store the reverse of the input number
	int axe; //to break portions of the input number in each loop
	//Prompt user to enter a positive number
	cout<<"Enter a positive number to check if it is Palindrome. Enter -1 to Exit"<<endl;
	cin>>number;
	//Program keeps looping untill user only enters -1 to exit
	while(number != -1){
	//Proceed if received number is positive
	if(number > 0){
	reversed_number = 0; //Reset the reverse of number
	axe = 1; //Reset axe
	do{
	/*Basically, append 0 to the right of number reverse, then add the last digit of
	the entered number after breaking an increasing portion in each loop iteration*/
	reversed_number = reversed_number * 10 + (number / axe % 10);
	//Increase axe value to increase the portion to be breaked from the entered number
	axe *= 10;
	}while(axe < number); //Exit loop once axe breaking portion is bigger than number length
	//Display the result by comparing entered number with its reverse
	cout<<">>Result: "<<number;
	if(reversed_number == number)
	cout<<" is Palindrome";
	else
	cout<<" is not Palindrome";
	cout<<endl<<endl;
	}
	//Prompt user to enter another positive number
	cout<<"Enter a positive number to check if it is Palindrome. Enter -1 to Exit"<<endl;
	cin>>number;
	}
	return 0;
	}

view raw gistfile1.cpp hosted with ❤ by GitHub

The nice thing here is that I didn't use a variable to copy the entered number. The code starts pulling each digit from the right and append them to the left of the reversed number in each loop iteration

I hope that I brought something useful, or provided you with a solution for your homework. See you next time with more number types.