Compilare: user.cpp: In function ‘void expand(std::pair<int, int>)’: user.cpp:62:13: warning: unused variable ‘val’ [-Wunused-variable] int val; ^ user.cpp: In function ‘int main()’: user.cpp:88:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j=0; j<S[i].size(); ++j) ^ user.cpp:98:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < S[i-d].size(); ++j) ^ user.cpp:104:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j=0; j<S[i].size(); ++j) ^ user.cpp:111:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j=0; j<S[i].size(); ++j) ^ user.cpp:84:9: warning: unused variable ‘j’ [-Wunused-variable] int j=maxv; ^