Compilare: user.cpp: In function ‘int bs(int, int)’: user.cpp:23:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (; step < sp[i].size(); step <<= 1); ^ user.cpp:25:59: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (sol - step >= 0 && sp[i][sol - step].first >= x) ^ user.cpp: In function ‘int main()’: user.cpp:63:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (now == sp[i].size()) ^