Compilare: user.cpp: In member function ‘void Tree::dfs(int)’: user.cpp:66:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (i - 1 >= dp[v].size()) ~~~~~~^~~~~~~~~~~~~~~ user.cpp: In function ‘int main()’: user.cpp:80:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:86:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &val); ^ user.cpp:94:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &u); ^