From 33e318d5168dd5e384790a997c308cddc1e30e15 Mon Sep 17 00:00:00 2001
From: Krutika <krutika4@users.noreply.github.com>
Date: Mon, 29 Oct 2018 21:23:58 -0400
Subject: [PATCH] Merge Sort Complete Implementation in C++

---
 Merge_Sort.cpp | 51 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 51 insertions(+)
 create mode 100644 Merge_Sort.cpp

diff --git a/Merge_Sort.cpp b/Merge_Sort.cpp
new file mode 100644
index 0000000..6e313ac
--- /dev/null
+++ b/Merge_Sort.cpp
@@ -0,0 +1,51 @@
+#include <iostream>
+#include <vector>
+using namespace std;
+
+void merge(vector<int>& a, vector<int>& temp, int leftPos, int rightPos, int rightEnd){
+    int leftEnd = rightPos - 1;
+    int tmpPos = leftPos;
+    int numElements = rightEnd - leftPos + 1;
+    
+    while(leftPos <= leftEnd && rightPos <= rightEnd)
+        if(a[leftPos] <= a[rightPos])
+            temp[tmpPos++] = std::move(a[leftPos++]);
+        else
+            temp[tmpPos++] = std::move(a[rightPos++]);
+    
+    while(leftPos <= leftEnd)       //Copy remaining first half
+        temp[tmpPos++] = std::move(a[leftPos++]);
+        
+    while(rightPos <= rightEnd)     ////Copy remaining second half
+        temp[tmpPos++] = std::move(a[rightPos++]);
+        
+    //Copy back temp array
+    for(int i=0; i<numElements; ++i, --rightEnd)
+        a[rightEnd] = std::move(temp[rightEnd]);
+}
+
+
+void mergeSort(vector<int>& a, vector<int>& temp, int left, int right){
+    if(left < right){
+        int center = (left + right) / 2;
+        mergeSort(a, temp, left, center);
+        mergeSort(a, temp, center+1, right);
+        merge(a, temp, left, center+1, right);
+    }
+}
+
+void mergeSort(vector<int>& a){
+    int size = a.size();
+    vector<int> temp(size);
+    mergeSort(a, temp, 0, size-1);
+}
+
+int main()
+{
+    vector<int> v1 = {2,4,1,6,7,36,23};
+    mergeSort(v1);
+    std::cout<<"Sorted array is:\n";
+    for(int i=0; i<v1.size(); i++)
+        std::cout<<v1[i]<<" ";
+    return 0;
+}