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  1. #include <iostream>
  2. using namespace std;
  3.  
  4. void merge(int arr[], int left, int mid, int right) {
  5.     int n1 = mid - left + 1;
  6.     int n2 = right - mid;
  7.  
  8.     int *L = new int[n1];
  9.     int *R = new int[n2];
  10.  
  11.     for (int i = 0; i < n1; i++) L[i] = arr[left + i];
  12.     for (int j = 0; j < n2; j++) R[j] = arr[mid + 1 + j];
  13.  
  14.     int i = 0, j = 0, k = left;
  15.  
  16.     while (i < n1 && j < n2) {
  17.         if (L[i] <= R[j]) {
  18.             arr[k++] = L[i++];
  19.         } else {
  20.             arr[k++] = R[j++];
  21.         }
  22.     }
  23.  
  24.     while (i < n1) arr[k++] = L[i++];
  25.     while (j < n2) arr[k++] = R[j++];
  26.  
  27.     delete[] L;
  28.     delete[] R;
  29. }
  30.  
  31. void mergeSort(int arr[], int left, int right) {
  32.     if (left < right) {
  33.         int mid = left + (right - left) / 2;
  34.  
  35.         mergeSort(arr, left, mid);
  36.         mergeSort(arr, mid + 1, right);
  37.  
  38.         merge(arr, left, mid, right);
  39.     }
  40. }
  41.  
  42. int main() {
  43.     int n;
  44.     cin >> n;
  45.     int arr[n];
  46.     for (int i = 0; i < n; i++) cin >> arr[i];
  47.  
  48.     mergeSort(arr, 0, n - 1);
  49.  
  50.     for (int i = 0; i < n; i++) cout << arr[i] << " ";
  51.     cout << endl;
  52.     return 0;
  53. }
Success #stdin #stdout 0.01s 5288KB
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stdin
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stdout
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https://ideone.com/ljvTAl
language:
C++ (gcc 8.3)
created:
2 days ago
visibility:
public

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