题解 | #合唱队#

//https://www.nowcoder.com/practice/6d9d69e3898f45169a441632b325c7b4?tpId=37&rp=1&ru=%2Fexam%2Foj%2Fta&qru=%2Fexam%2Foj%2Fta&sourceUrl=%2Fexam%2Foj%2Fta%3Fpage%3D1%26pageSize%3D50%26search%3D50%26tpId%3D37%26type%3D37&difficulty=&judgeStatus=&tags=&title=24&gioEnter=menu

#include <iostream>
#include <vector>

using namespace std;

int main() {
    int n = 0;
    while(cin >> n){
        vector<int> height(n, 0);
        int maxn = 0;
        int dp1[n], dp2[n];

        for(int i = 0;i<n;i++)
            cin >> height[i];

        for(int i = 0;i<n;i++){
            dp1[i] = 1;
            for(int j = 0;j<i;j++)
                if(height[j]<height[i])
                    dp1[i] = max(dp1[i], dp1[j]+1);
        }

        for(int i = n-1;i>=0;i--){
            dp2[i] = 1;
            for(int j = n-1;j>i;j--)
                if(height[j]<height[i])
                    dp2[i] = max(dp2[i], dp2[j]+1);
        }

        for(int i = 0;i<n;i++)
            maxn = max(maxn, dp1[i]+dp2[i]-1);

        cout << n-maxn;

    }
}