Compilare: main.cpp: In function 'int main()': main.cpp:98:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i = 0 ; i < units.size() ; i++) ~~^~~~~~~~~~~~~~ main.cpp:99:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j = 0 ; j < v[last].size() ; j++){ ~~^~~~~~~~~~~~~~~~ main.cpp:115:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j = u + 2 ; j <= v[last].size() + u + 1 ; j++){ ~~^~~~~~~~~~~~~~~~~~~~~~~~~ main.cpp:96:9: warning: variable 'it' set but not used [-Wunused-but-set-variable] int it,its; ^~