二分查找法，查詢指定的值

#include
#include<stdlib.h>
int main()
{
int a[10] = { 1,3,5,7,8,9,10,15,17,18 };
int n = 16;
int start = 0;
int end = 9;
int middle = (start + end) / 2;
int count = 0;
while (1)   //二分查找法，查找排好序裏面的指定值
{
count++;
if (a[middle] == n)
{
printf("查找值：%d   查找次數： %d\n", a[middle],count);
break;
}
else if (a[middle] < n)
{
start = middle + 1;
middle = (start + end) / 2;
}
else
{
end = middle - 1;
middle = (start + end) / 2;
}
if (start >= end)
{
printf("沒有找到該數%d  查找次數： %d \n", n,count);
break;
}
}
printf("查找完畢\n");
system("pause");
return 0;

}

效果圖：