merge_sort.cpp

Problem Solving/merge_sort.cpp

@@ -0,0 +1,44 @@
+#include<iostream>
+using namespace std;
+void merge(int arr[],int start1,int start2,int end){
+    int k = start1;
+    int m = start2-1;
+    int n = end;
+    int temp[100];
+    int index=0;
+    while(start1<=m && start2<=n){
+        if(arr[start1]<arr[start2]){
+            temp[index++] = arr[start1++];
+        }else{
+            temp[index++] = arr[start2++];
+        }
+    }
+    while(start1<=m){
+        temp[index++] = arr[start1++];
+    }
+     while(start2<=n){
+        temp[index++] = arr[start2++];
+    }
+    for(int i=0;i<index;i++){
+        arr[k+i] = temp[i];
+    }
+    return;
+}
+void mergeSort(int arr[],int start,int end){
+    if(start>=end){
+        return;
+    }
+    int mid = (start+end)/2;
+    mergeSort(arr,start,mid);
+    mergeSort(arr,mid+1,end);
+    merge(arr,start,mid+1,end);
+    return;
+}
+int main(){
+int arr[100] = {5,1,7,2,9};
+mergeSort(arr,0,4);
+for(int i=0;i<5;i++){
+    cout<<arr[i]<<" ";
+}
+cout<<endl;
+}