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mergeSort.cpp
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mergeSort.cpp
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// { Driver Code Starts
#include <stdio.h>
#include <bits/stdc++.h>
using namespace std;
/* Function to print an array */
void printArray(int arr[], int size)
{
int i;
for (i=0; i < size; i++)
printf("%d ", arr[i]);
printf("\n");
}
// } Driver Code Ends
class Solution
{
public:
void merge(int arr[], int l, int m, int r)
{
// Your code here
auto const len1 = m-l+1;
auto const len2 = r-m;
auto *leftArray = new int[len1], *rightArray = new int[len2];
for(auto i=0; i<len1; ++i)
leftArray[i] = arr[l+i];
for(auto j=0; j<len2; ++j)
rightArray[j] = arr[m+1+j];
auto idx1 = 0, idx2 = 0;
int idx3 = l;
while(idx1 < len1 && idx2 < len2) {
if(leftArray[idx1] <= rightArray[idx2]) {
arr[idx3] = leftArray[idx1];
idx1++;
}
else {
arr[idx3] = rightArray[idx2];
idx2++;
}
idx3++;
}
while(idx1 < len1) {
arr[idx3] = leftArray[idx1];
idx1++; idx3++;
}
while(idx2 < len2) {
arr[idx3] = rightArray[idx2];
idx2++; idx3++;
}
}
public:
void mergeSort(int arr[], int l, int r)
{
//code here
if(l>=r) return;
auto m = l+(r-l)/2;
mergeSort(arr, l, m);
mergeSort(arr, m+1, r);
merge(arr, l, m, r);
}
};
// { Driver Code Starts.
int main()
{
int n,T,i;
scanf("%d",&T);
while(T--){
scanf("%d",&n);
int arr[n+1];
for(i=0;i<n;i++)
scanf("%d",&arr[i]);
Solution ob;
ob.mergeSort(arr, 0, n-1);
printArray(arr, n);
}
return 0;
} // } Driver Code Ends