Compilare: user.cpp: In function ‘int main()’: user.cpp:29:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < s.size(); i++) ~~^~~~~~~~~~ user.cpp:32:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = i; j < s.size(); j++) ~~^~~~~~~~~~ user.cpp:57:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < s.size(); i++) ~~^~~~~~~~~~ user.cpp:59:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < rev[i].size(); j++) ~~^~~~~~~~~~~~~~~ user.cpp:62:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < nou[i].size(); j++) ~~^~~~~~~~~~~~~~~