Compilare: user.cpp: In function ‘void biconex(int, int, int)’: user.cpp:19:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < l[x].size(); ++i) { ~~^~~~~~~~~~~~~ user.cpp: In function ‘int main()’: user.cpp:60:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < bic.size(); ++i) { ~~^~~~~~~~~~~~ user.cpp:62:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < bic[i].size(); ++j) ~~^~~~~~~~~~~~~~~