Compilare: main.cpp: In function 'void print()': main.cpp:20:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( i = 0 ; i < q.size() ; ++ i ) out << q[ i ].first << q[ i ].second ; ~~^~~~~~~~~~ main.cpp:29:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( i = 0 ; i < l.size() ; ++ i ) ~~^~~~~~~~~~ main.cpp:32:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( i = 0 ; i < q.size() ; ++ i ) out << q[ i ].first << q[ i ].second ; ~~^~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:48:9: warning: unused variable 'i' [-Wunused-variable] int i , j ; ^ main.cpp:48:13: warning: unused variable 'j' [-Wunused-variable] int i , j ; ^