二分查找

2019-05-17

00:51:23

https://www.cnblogs.com/ECJTUACM-873284962/p/6361271.html

终于比大佬多了解了点

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int a[100];
    int i,j;
    int n;
    scanf ("%d", &n);
    for (i = 0; i < n; i++)
    {
        scanf("%d", &a[i]);
    }
    int x;
    scanf ("%d", &x);
    cout << lower_bound(a, a + n, x) - a; //从0开始
    cout << upper_bound(a, a + n, x) - a;
    return 0;
}