日期:2014-05-16  浏览次数:20725 次

二分法实现插入排序,时间复杂度O(nlgn),算法导论练习2.3,linux纯C实现
#include <stdio.h>
int binarySearch(int* a, int fI, int lI, int N)
{
	int mI = (fI+lI) >> 1;
	if (N > *(a+mI))
	{
		fI = mI + 1;
		if(fI > lI)
			return mI+1;
		binarySearch(a, fI, lI, N);
	}
	else if (N < *(a+mI))
	{
		lI = mI - 1;
		if(fI > lI)
			return mI;
		binarySearch(a, fI, lI, N);
	}
	else
		return mI+1;
}
void insertSort(int* a, int index, int N)
{
	int key = *(a+index);
	if(index+1 <= N)
	{
		int i = binarySearch(a, 0, index-1, key);
		int j = index-1;
		for (;j>=i;j--)
		{
			*(a+j+1) = *(a+j);
		}
		*(a+i) = key;
		insertSort(a, index+1, N);
	}
	return;
}
int main()
{
	int a[10] = {212,343,534,2,3,67,34,78,90,32};
	int L = sizeof(a)/sizeof(int);
	int i = 0;
	insertSort(a, 1, L);
	for (;i<L;i++)
		printf("%d ",*(a+i));
	printf("\n");
	return 0;
}