Compilare: user.cpp: In function ‘void update(int, int, int)’: user.cpp:24:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( ; pos < A[ind].size(); pos += pos ^ (pos & (pos - 1))) ^ user.cpp: In function ‘int main()’: user.cpp:58:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < w[i].size(); ++j) { ^ user.cpp:69:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 1; j < z[i].size(); ++j) ^ user.cpp:74:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < z[i].size(); ++j) ^