运行 ID: 86989

Main.cc: In function ‘int main()’:
Main.cc:11:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int i = 0; i < s.size(); i++) {
                     ~~^~~~~~~~~~
Main.cc:17:5: error: ‘reverse’ was not declared in this scope
     reverse(s.begin(), s.end());
     ^~~~~~~
Main.cc:20:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int i = 0; i < s.size(); i++) {
                     ~~^~~~~~~~~~