没参加笔试，贴个第三题代码（不知道有没有BUG...）~~ 希望自己的笔试的时候题也简单点🤣 void fun(string &str, int x) { vector<vector<char>> v; int l = 0, r = x - 1; int add_l = 1, add_r = -1; int k = 0, n = str.size(); while(k < n){ vector<char> tmp(x, ' '); if(l == r){ add_l = -1; add_r = 1; tmp[l] = str[k++]; l--, r++; v.push_back(tmp); continue; } if(l == 0){ add_l = 1; add_r = -1; } tmp[l] = str[k++]; if(k == n){ v.push_back(tmp); break; } tmp[r] = str[k++]; v.push_back(tmp); l += add_l; r += add_r; } int m = v.size(); for(int i = 0; i < x; i++) for(int j = 0; j < m; j++){ if(v[j][i] != ' ') cout<<v[j][i]; } cout<<endl; }