• 链接：https://www.acwing.com/problem/content/1019/

算法

 两次LIS，一次正向，一次反向。

代码

#include <iostream>
using namespace std;

const int N = 110;
int k, n;
int w[N], f[N];


int main() {
    cin >> k;
    while (k--) {
        cin >> n;
        
        for (int i = 1; i <= n; ++i) cin >> w[i];
        int res = 0;
        for (int i = 1; i <= n; ++i) {
            f[i] = 1;
            for (int j = 1; j < i; ++j) {
                if (w[i] > w[j]) f[i] = max(f[i], f[j] + 1);
            }
            res = max(res, f[i]);
        }
        
        for (int i = n; i >= 1; --i) {
            f[i] = 1;
            for (int j = n; j > i; --j) {
                if (w[i] > w[j]) f[i] = max(f[i], f[j] + 1);
            }
            res = max(res, f[i]);
        }
        cout << res << endl;
    }
    return 0;
}

Acwing-----1017. 怪盗基德的滑翔翼