병합정렬 구현

1 C

#include <stdio.h>
void merge_sort(int arr[], int size, int low, int high) {
	if(low >= high) return;
	int mid = (low+high)/2;
	merge_sort(arr, size, low, mid);
	merge_sort(arr, size, mid+1, high);
	
	//merge
    int temp[size-1], l1, l2, i;
	for(l1=low, l2=mid+1, i=low; l1<=mid && l2<=high; i++) {
		if(arr[l1]<=arr[l2]) temp[i]=arr[l1++];
		else temp[i]=arr[l2++];
	}
	while(l1 <= mid) temp[i++]=arr[l1++];
	while(l2 <= high) temp[i++]=arr[l2++];
	for(i=low; i<=high; i++) arr[i]=temp[i];
}
int main() {
    int arr[] = {3,4,2,1,7,5,8,9,0,6,100,10};
    int size = sizeof(arr)/sizeof(int);
	merge_sort(arr, size, 0, size-1);
	for(int i=0; i<size; i++) printf("%d ", arr[i]);
	// 0 1 2 3 4 5 6 7 8 9 10 100 
}

2 같이 보기

• 정렬 구현
• 병합정렬