题解 | #合唱队#

#include <algorithm>
#include <iostream>
#include <vector>
using namespace std;

int main() {
    int N;
    while (cin >> N) { // 注意 while 处理多个 case
        vector<int> array(N);
        for (int i = 0; i < N; i++) {
            cin >> array[i];
        }
        vector<int> left(N, 0);
        for (int i = 0; i < N; i++) {
            for (int j = 0; j < i; j++) {
                if (array[j] < array[i]) {
                    left[i] = max(left[i], left[j] + 1);
                }
            }
        }
        vector<int> right(N, 0);
        for (int i = N-1; i >=0; i--) {
            for (int j = N-1; j > i; j--) {
                if (array[i] > array[j]) {
                    right[i] = max(right[i], right[j] + 1);
                }
            }
        }
        int max_stay = 0;
        for (int i = 1; i <= N - 2; ++i) {
            max_stay = max(max_stay, left[i] + right[i] + 1);
        }
        cout << N - max_stay << endl;
    }
}
// 64 位输出请用 printf("%lld")