fork download
copy 
  1. #include <stdio.h> 
  2. #include <stdlib.h> 
  3.  
  4. // Merges two subarrays of arr[]. 
  5. // First subarray is arr[l..m] 
  6. // Second subarray is arr[m+1..r] 
  7. void merge(int arr[], int l, int m, int r) 
  8. { 
  9.     int i, j, k; 
  10.     int n1 = m - l + 1; 
  11.     int n2 = r - m; 
  12.  
  13.     /* create temp arrays */
  14.     int L[n1], R[n2]; 
  15.  
  16.     /* Copy data to temp arrays L[] and R[] */
  17.     for (i = 0; i < n1; i++) 
  18.         L[i] = arr[l + i]; 
  19.     for (j = 0; j < n2; j++) 
  20.         R[j] = arr[m + 1 + j]; 
  21.  
  22.     /* Merge the temp arrays back into arr[l..r]*/
  23.     i = 0; // Initial index of first subarray 
  24.     j = 0; // Initial index of second subarray 
  25.     k = l; // Initial index of merged subarray 
  26.     while (i < n1 && j < n2) { 
  27.         if (L[i] <= R[j]) { 
  28.             arr[k] = L[i]; 
  29.             i++; 
  30.         } 
  31.         else { 
  32.             arr[k] = R[j]; 
  33.             j++; 
  34.         } 
  35.         k++; 
  36.     } 
  37.  
  38.     /* Copy the remaining elements of L[], if there 
  39.        are any */
  40.     while (i < n1) { 
  41.         arr[k] = L[i]; 
  42.         i++; 
  43.         k++; 
  44.     } 
  45.  
  46.     /* Copy the remaining elements of R[], if there 
  47.        are any */
  48.     while (j < n2) { 
  49.         arr[k] = R[j]; 
  50.         j++; 
  51.         k++; 
  52.     } 
  53. } 
  54.  
  55. /* l is for left index and r is right index of the 
  56.    sub-array of arr to be sorted */
  57. void mergeSort(int arr[], int l, int r) 
  58. { 
  59.     if (l < r) { 
  60.         // Same as (l+r)/2, but avoids overflow for 
  61.         // large l and h 
  62.         int m = l + (r - l) / 2; 
  63.  
  64.         // Sort first and second halves 
  65.         mergeSort(arr, l, m); 
  66.         mergeSort(arr, m + 1, r); 
  67.  
  68.         merge(arr, l, m, r); 
  69.     } 
  70. } 
  71.  
  72. /* UTILITY FUNCTIONS */
  73. /* Function to print an array */
  74. void printArray(int A[], int size) 
  75. { 
  76.     int i; 
  77.     for (i = 0; i < size; i++) 
  78.         printf("%d ", A[i]); 
  79.     printf("\n"); 
  80. } 
  81.  
  82. /* Driver program to test above functions */
  83. int main() 
  84. { 
  85.     int arr[] = { 12, 11, 13, 5, 6, 7 }; 
  86.     int arr_size = sizeof(arr) / sizeof(arr[0]); 
  87.  
  88.     printf("Given array is \n"); 
  89.     printArray(arr, arr_size); 
  90.  
  91.     mergeSort(arr, 0, arr_size - 1); 
  92.  
  93.     printf("\nSorted array is \n"); 
  94.     printArray(arr, arr_size); 
  95.     return 0; 
  96. }
Success #stdin #stdout 0s 4472KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
Given array is 
12 11 13 5 6 7 

Sorted array is 
5 6 7 11 12 13
https://ideone.com/rimfoQ
language:
C (gcc 8.3)
created:
3 years ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!