#include<iostream> #include<vector> #include<algorithm> using namespace std; int main() { int len = 0; cin >> len; vector<int> arr(len, 0); for (int i = 0; i < len; ++i) { cin >> arr[i]; } int u = 0; int index = 1;//代表索引为1 //首先生成变量u, arr[0,...u]表示在区间[0, u]上无重复并...