Compilare: user.cpp: In function ‘void updateStk(std::vector<int>*, int, int)’: user.cpp:20:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (where >= stk -> size()) { ^ user.cpp:22:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (stk -> size() > ans) ^ user.cpp: In function ‘std::vector<int>* uniteLis(std::vector<int>*, std::vector<int>*)’: user.cpp:77:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < lisStk1 -> size(); ++ i) ^ user.cpp:84:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < lisStk2 -> size(); ++ i) ^ user.cpp: In function ‘std::vector<int>* uniteLds(std::vector<int>*, std::vector<int>*)’: user.cpp:94:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < ldsStk1 -> size(); ++ i) ^ user.cpp:101:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < ldsStk2 -> size(); ++ i) ^ user.cpp: In function ‘void dfs(int, int)’: user.cpp:133:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i < graph[node].size(); ++ i) { ^ user.cpp:141:46: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < lis1 -> size(); ++ i) { ^ user.cpp:147:46: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < lds2 -> size(); ++ i) { ^ user.cpp:154:46: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < lis2 -> size(); ++ i) { ^ user.cpp:160:46: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < lds1 -> size(); ++ i) { ^