技術標籤：機試準備

#include<stdio.h>
int lower_bound(int A[], int left, int right, int x)
{   // 找第一個大於等於 x 的位置 
	int mid;
	while(left < right)
	{
		mid = (left + right) / 2;
		if(A[mid] >= x) right = mid;
		else left = mid + 1;
	}
	return left;
}
int upper_bound(int A[], int left, int right, int
 
 x)
{
	// 找第一個大於 x 的位置
	int mid;
	while(left < right)
	{
	    mid = (left + right) / 2;
		if(A[mid] > x) right = mid;
		else left = mid + 1;	
	} 
	return left;
}
int main()
{
    const int n = 5;
    int A[n] = {1, 3, 3, 3, 6};
    printf("%d %d", lower_bound(A, 0, 4, 3), upper_bound(A, 0
 
, 4, 3));
	return 0;
}