Compilare: user.cpp: In function ‘void BF(int, int*&, int*&, int*&)’: user.cpp:24:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < la[val].size(); i++) { ~~^~~~~~~~~~~~~~~~ user.cpp: In function ‘void read()’: user.cpp:38:9: warning: unused variable ‘m’ [-Wunused-variable] int n, m, x, y; ^