Compilare: main.cpp: In function 'int main()': main.cpp:55:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( k = 0; k < vec[v[j]].size ( ); k++ ){ ~~^~~~~~~~~~~~~~~~~~~~ main.cpp:73:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( k = 0; k < vec[v[i]].size ( ); k++ ) ~~^~~~~~~~~~~~~~~~~~~~ main.cpp:75:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( k = 0; k < vec[v[i]].size ( ); k++ ){ ~~^~~~~~~~~~~~~~~~~~~~