Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:31:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0;i < v[nod].size();i++) { ~~^~~~~~~~~~~~~~~ user.cpp: In function ‘int main()’: user.cpp:38:32: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d%d", &n, &m); ^ user.cpp:41:33: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d", &elem); ^ user.cpp:53:36: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d%d", &x, &y); ^