chore(CPlusPlus): add palindrome (#483)

Co-authored-by: Rahul Rajeev Pillai <66192267+Ashborn-SM@users.noreply.github.com>

algorithms/CPlusPlus/Maths/palindrome.cpp

@@ -0,0 +1,21 @@
+// Program to find whether a number and word is palindrome or not.
+
+#include<iostream>				//header file
+using namespace std;
+int main()						//Main function
+{
+	string num_str = "";		//define variable
+	cin >> num_str;				//taking input from user
+	string new_str = "";		//define a new variable
+
+	for(int x = (num_str.size()-1); x >= 0; x--){		//for loop started
+		new_str += num_str[x];							//assigning the value input by user to new variable in reverse order
+	}													//for loop end
+
+	cout << (num_str == new_str ? "palindrome" : "Non-palindrome");			//checking whether the value assigned to both variables is equal or not using ternary operator and printing whether it's palindrome or non-palindrome
+
+	return 0;					//returning the main function
+}
+
+//complexity of the program is O(n)
+//test cases:- 101,pop,asdfgfdsa,123454321,obobo,nancyiycnan etc.

algorithms/CPlusPlus/README.md

@@ -123,7 +123,8 @@
 3. [Prime Sieve](Maths/prime-sieve.cpp)
 4. [Fibonacci Series](Maths/fibonaccci-series.cpp)
 5. [Armstrong Number](Maths/armstrong.cpp)
-6. [Reverse digit of a number](Maths/reverse-digits.cpp)
+6. [Palindrome](Maths/palindrome.cpp)
+7. [Reverse digit of a number](Maths/reverse-digits.cpp)
 
 # Recursion
 

docs/en/Strings/Palindrome.md

@@ -22,6 +22,7 @@ A palindrome is a word, phrase, number or sequence of words that reads the same
 
 ## Implementation
 - [C](../../../algorithms/C/strings/palindrome.c)
+- [C++](../../../algorithms/CPlusPlus/Maths/palindrome.cpp)
 - [C#](../../../algorithms/CSharp/src/Strings/palindrome.cs)
 - [Haskell](../../../algorithms/Haskell/strings/palindrome.hs)
 - [Java](../../../algorithms/Java/strings/palindrome.java)

docs/ja/Strings/Palindrome.md

@@ -21,6 +21,7 @@
 
 ## 実装
 - [C](../../../algorithms/C/strings/palindrome.c)
+- [C++](../../../algorithms/CPlusPlus/Maths/palindrome.cpp)
 - [C#](../../../algorithms/CSharp/src/Strings/palindrome.cs)
 - [Haskell](../../../algorithms/Haskell/strings/palindrome.hs)
 - [Java](../../../algorithms/Java/strings/palindrome.java)

docs/zh-tw/Strings/Palindrome.md

@@ -20,6 +20,7 @@
 
 ## 程式碼
 - [C](../../../algorithms/C/strings/palindrome.c)
+- [C++](../../../algorithms/CPlusPlus/Maths/palindrome.cpp)
 - [C#](../../../algorithms/CSharp/src/Strings/palindrome.cs)
 - [Haskell](../../../algorithms/Haskell/strings/palindrome.hs)
 - [Java](../../../algorithms/Java/strings/palindrome.java)