归并排序

 

#include <stdio.h>
#include <string.h>

int a[9] = {0,49,38,65,97,76,13,27};
int b[9];

void merge(int s, int m, int t) 
{
	int		i, j, k;

	k = s;
	for (i = s, j = m+1; i <= m && j <= t; ) {
		if (a[i] < a[j]) {
			b[k++] = a[i++];
		}
		else {
			b[k++] = a[j++];
		}
	}
	for (; i <= m; i++) {
		b[k++] = a[i];
	}
	for (; j <= t; j++) {
		b[k++] = a[j];
	}
	for (i = s; i <= t; i++) {
		a[i] = b[i];
	}
}

void merge_sort(int s, int t)
{
	int		m, i;

	printf("sort (%d, %d)\n", s, t); 
	if (s < t) {
		m = (s+t) / 2;
		merge_sort(s, m);
		merge_sort(m+1, t);
		merge(s, m, t);
	}
}

int main()
{
	int		i;

	merge_sort(1, 7);
	for (i = 1; i <= 7; i++) {
		printf("%d ", a[i]);
	}
	printf("\n");
	getchar();
	return 0;
}