#include <iostream> #include <tuple> using namespace std; int main() { string s; int t, l; cin >> t; while (t--) { cin >> l; cin.ignore(); //getchar();忽略换行符 getline(cin, s); for (int i = s.size() - 1; i >= 0; i--)if (s[i] != ' ') cout << s[i]; cout << endl; } r...