Compilare: user.cpp: In function ‘void dfs(int, int)’: user.cpp:7:79: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] user.cpp:8:65: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] user.cpp: In function ‘int main()’: user.cpp:15:120: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] user.cpp:14:30: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] user.cpp:14:66: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] user.cpp:14:86: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] user.cpp:14:125: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] user.cpp:15:40: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] user.cpp:17:12: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]