#include <iostream> #include <vector> #include <string> #include <list> #include <queue> #include <unordered_map> #include <algorithm> using namespace std; long long a[10010]; long long b[10010]; long long dp[10010][10010]; int main() { int n; long long sum = 0; cin >> n; for (int i = 0; i < n; i++) { cin >> a[i]; b[n - 1 - i] = a[i]; sum += a[i]; } for (int i = 1; i <= n; i++) { for (int j = 1; j <= n; j++) { if (a[i - 1] == b[j - 1]) dp[i][j] = dp[i - 1][j - 1] + a[i - 1]; else dp[i][j] = std::max(dp[i][j - 1], dp[i - 1][j]); } } cout << sum + sum - dp[n][n] << endl; return 0; } 第二题dp，AC