02331_数据结构_第8章_查找

8.2顺序表的查找

8.2.2二分查找

#define _CRT_SECURE_NO_WARNINGS

#include<stdio.h>
#include<stdlib.h>

main()
{
    int a[1024];
    int i;

    for (i = 0;i < 1024;i++)
    {
        a[i] = i;
    }

    int num = 998;
    int shang = 0;
    int xia = 1023;
    int zhong;
    int flag = 0;

    while (shang <= xia)
    {
        zhong = (shang + xia) / 2;
        printf("shang=%d,zhong=%d,xia=%d
", shang, zhong, xia);

        if (num == a[zhong])
        {
            flag = 1;
            break;
        }
        else if (num>a[zhong])
        {
            shang = zhong + 1;
        }
        else
        {
            xia = zhong - 1;
        }
    }

    if (flag == 1)
    {
        printf("找到
");
    }
    else
    {
        printf("没有找到
");
    }

    system("pause");
}