【算法】【归并排序】

#include<stdio.h>

static int merge(int *temp, int *arr, int start, int mid, int end)
{
	int i = 0;
	int j = 0;
	int k = 0;
	i = start;
	j = mid+1;
	while(i<=mid&&j<=end){
		if(arr[i]<arr[j])
			temp[k++] =arr[i++];
		else
			temp[k++] = arr[j++];
	}
	while(i<=mid){
		temp[k++] =arr[i++];
	}
	while(j<=end){
		temp[k++] = arr[j++];
	}
	printf("merge\t");
	for(i=0; i<k; i++){
		printf("%d\t", temp[i]);
	}
	printf("\n");
	k = 0;
    while(start <= end){
        arr[start++] = temp[k++];
    }
}
static int sort(int *arr, int start, int end, int *temp)
{
	int i = 0;
	for(i=start; i<=end; i++){
		printf("%d\t", arr[i]);
	}
	printf("\n");
	if(arr!=NULL&&end>start){
		int mid = (start + end)/2;
		//if(mid>start)
			sort(arr, start, mid, temp);
		//if(mid+1<end)
			sort(arr, mid+1, end, temp);
			merge(temp, arr, start, mid, end);
	}
	return 0;
}
int main()
{
	int arr[] = {8,4,5,7,1,3,6,2};
	int temp[sizeof(arr)/sizeof(arr[0])];
	sort(arr, 0, sizeof(arr)/sizeof(arr[0])-1, temp);
	
	int i = 0;
	for(i=0; i<sizeof(arr)/sizeof(arr[0]); i++){
		printf("%d\t", temp[i]);
	}
	printf("\n");
}