Compilare: user.cpp: In member function ‘void Tree::dfs(int)’: user.cpp:71:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (i - 1 > dp[v].size()) break; ~~~~~~^~~~~~~~~~~~~~ user.cpp:72:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (i - 1 == dp[v].size()) ~~~~~~^~~~~~~~~~~~~~~ user.cpp: In function ‘int main()’: user.cpp:96:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:102:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &val); ^ user.cpp:110:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &u); ^