89 lines
1.8 KiB
C
89 lines
1.8 KiB
C
#include <stdio.h>
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#include <stdlib.h>
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void merging(int a[], int l, int m, int r);
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void mergeSort(int a[], int l, int r);
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// Driver code
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int main()
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{
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int n;
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printf("Enter the size of the array:\n");
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scanf("%d", &n);
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int a[n];
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printf("Enter the elements of the array:\n");
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for (int i = 0; i < n; i++)
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scanf("%d", &a[i]);
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printf("Given array is: ");
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for (int i = 0; i < n; i++)
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printf("%d ", a[i]);
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mergeSort(a, 0, n - 1);
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printf("\nSorted array is: ");
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for (int i = 0; i < n; i++)
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printf("%d ", a[i]);
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return 0;
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}
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// Merges two subarrays of a[].
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// First subarray is a[l..m]
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// Second subarray is a[m+1..r]
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void merging(int a[], int l, int m, int r)
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{
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int n1 = m - l + 1;
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int n2 = r - m;
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int Left[n1], Right[n2]; // Creating temporary arrays
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// Copy data to temp arrays Left[] and Right[]
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for (int i = 0; i < n1; i++)
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Left[i] = a[l + i];
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for (int j = 0; j < n2; j++)
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Right[j] = a[m + 1 + j];
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int p = 0, q = 0, k = l;
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while (p < n1 && q < n2)
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{
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if (Left[p] <= Right[q])
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{
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a[k] = Left[p];
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p++;
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}
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else
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{
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a[k] = Right[q];
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q++;
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}
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k++;
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}
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// Copy the remaining elements of
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// Left[], if there are any
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while (p < n1)
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{
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a[k] = Left[p];
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p++;
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k++;
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}
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// Copy the remaining elements of
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// Right[], if there are any
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while (q < n2)
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{
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a[k] = Right[q];
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q++;
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k++;
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}
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}
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// l is for left index and r is
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// right index of the sub-array
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// of arr to be sorted
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void mergeSort(int a[], int l, int r)
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{
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if (l < r)
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{
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int m = l + (r - l) / 2;
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mergeSort(a, l, m);
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mergeSort(a, m + 1, r);
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merging(a, l, m, r);
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}
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}
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