E - Average and Median

原创

whiteawll 2022-08-16 14:49:14 博主文章分类：练习题目 ©著作权

文章标签 动态规划排序算法算法 i++ #include 文章分类 后端开发

©著作权归作者所有：来自51CTO博客作者whiteawll的原创作品，请联系作者获取转载授权，否则将追究法律责任

https://atcoder.jp/contests/abc236/tasks/abc236_e
#include<iostream>
#include<cmath>
using namespace std;

const int N = 1e3 + 10;
int a[N], b[N];
int n;

template <class T> bool check(T tar, T b[]) {
    T f = 0, g = 0;
    for (int i =1; i<= n; i++) {
        T t = max (f, g) + b[i];
        g = f;
        f = t;
    }
    return max (f, g) >= 0;
}
int main () {
    cin >> n;
    for (int i =1; i<= n; i ++) cin >> a[i];
    double l = 1.0, r = 1e9 * 1.0;
    while ((r - l) / l > 1e-7) {
        double mid = sqrt(r * l);
        double b[N];
        for (int i = 1; i <= n ;i ++)        
            b[i] = a[i] - mid;
        if (check(mid, b)) r = mid;
        else l = mid;
    }
    cout << l << endl;
    int l1 = 0, r1 = 1e9;
    while (l < r ) {
        int mid = l1 + r1>> 1;
        int b[N];
        for (int i = 1; i <= n; i++)
            if (a[i] >= mid) b[i] = 1;
            else b[i] = -1;
        if (check(mid, b)) r1 = mid;
        else l1 = mid + 1;
    }
    cout << l1 << endl;
    return 0;
}