Compilare: main.cpp: In function 'void firsttrav(int)': main.cpp:16:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<direct[node].size(); i++) { ~^~~~~~~~~~~~~~~~~~~~ main.cpp: In function 'void secondtrav(int)': main.cpp:27:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<reciproc[node].size(); i++) { ~^~~~~~~~~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:55:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<ctc.size(); i++) ~^~~~~~~~~~~