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  1. #include <iostream>
  2. #include <vector>
  3.  
  4. using namespace std;
  5.  
  6. const int N = (int)20;
  7.  
  8. int a[N];
  9. vector<int> aux;
  10.  
  11. void merge(vector<int> v1, vector<int> v2) {
  12.   int i = 0, j = 0;
  13.  
  14.   while(i < v1.size() && j < v2.size()) {
  15.     if (v1[i] <= v2[j]) aux.push_back(v1[i++]);
  16.     else aux.push_back(v2[j++]);
  17.   }
  18.  
  19.   while(i < v1.size()) aux.push_back(v1[i++]);
  20.   while(j < v2.size()) aux.push_back(v2[j++]);
  21. }
  22.  
  23. void merge_sort(int left, int right) {
  24.   if (left >= right) return;
  25.  
  26.   int mid = (left + right) / 2;
  27.  
  28.   vector<int> l, r;
  29.  
  30.   merge_sort(left, mid);
  31.   merge_sort(mid + 1, right);
  32.  
  33.   for(int i = left; i <= mid; i++) l.push_back(a[i]);
  34.   for(int i = mid+1; i <= right; i++) r.push_back(a[i]);
  35.  
  36.   aux.clear();
  37.   merge(l, r);
  38.  
  39.   for(int i = left; i <= right; i++) {
  40.     a[i] = aux[i - left];
  41.   }
  42.  
  43. }
  44.  
  45. int main() {
  46.   for(int i =0 ; i < N; i++) {
  47.     a[i] = rand() % 1001;
  48.  
  49.     if (i < 20)
  50.       cout << a[i] << " ";
  51.   }
  52.   cout << endl << endl << endl;
  53.  
  54.   merge_sort(0, N - 1);
  55.  
  56.   for(int i = 0; i < 20; i++) {
  57.     cout << a[i] << " ";
  58.   }
  59.   cout << endl;
  60. }
  61.  
Success #stdin #stdout 0.01s 5280KB
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stdin
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Standard input is empty
stdout
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897 802 765 992 1 521 220 380 729 969 184 887 104 641 909 378 724 582 387 583 


1 104 184 220 378 380 387 521 582 583 641 724 729 765 802 887 897 909 969 992
https://ideone.com/avizeQ
language:
C++14 (clang 8.0)
created:
12 days ago
visibility:
public

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