Added a Cpp program (Check if stack elements are pairwise consecutive)

C++/check if stack elements are pairwise consecutive_Mrinalini99.cpp

@@ -0,0 +1,76 @@
+// C++ program to check if successive 
+// pair of numbers in the stack are 
+// consecutive or not 
+#include <bits/stdc++.h> 
+using namespace std; 
+
+// Function to check if elements are 
+// pairwise consecutive in stack 
+bool pairWiseConsecutive(stack<int> s) 
+{ 
+	// Transfer elements of s to aux. 
+	stack<int> aux; 
+	while (!s.empty()) { 
+		aux.push(s.top()); 
+		s.pop(); 
+	} 
+
+	// Traverse aux and see if 
+	// elements are pairwise 
+	// consecutive or not. We also 
+	// need to make sure that original 
+	// content is retained. 
+	bool result = true; 
+	while (aux.empty() > 1) { 
+
+		// Fetch current top two 
+		// elements of aux and check 
+		// if they are consecutive. 
+		int x = aux.top(); 
+		aux.pop(); 
+		int y = aux.top(); 
+		aux.pop(); 
+		if (abs(x - y) != 1) 
+		result = false; 
+
+		// Push the elements to original 
+		// stack. 
+		s.push(x); 
+		s.push(y); 
+	} 
+
+	if (aux.size() == 1) 
+		s.push(aux.top()); 
+
+	return result; 
+} 
+
+// Driver program 
+int main() 
+{ 
+	stack<int> s; 
+	s.push(4); 
+	s.push(5); 
+	s.push(-2); 
+	s.push(-3); 
+	s.push(11); 
+	s.push(10); 
+	s.push(5); 
+	s.push(6); 
+	s.push(20); 
+
+	if (pairWiseConsecutive(s)) 
+		cout << "Yes" << endl; 
+	else
+		cout << "No" << endl; 
+
+	cout << "Stack content (from top)"
+		" after function call\n"; 
+	while (s.empty() == false) 
+	{ 
+	cout << s.top() << " "; 
+	s.pop(); 
+	} 
+
+	return 0; 
+} 

CONTRIBUTORS.md

@@ -83,3 +83,5 @@
 
 * [Bhashitha Dhananjaya](https://github.com/glbdhananjaya)
 
+* [Mrinalini Singh](https://github.com/Mrinalini99)
+