Compilare: user.cpp: In function ‘int dfs(int)’: user.cpp:14: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int dfs2(int, int)’: user.cpp:26: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:124: warning: comparison between signed and unsigned integer expressions user.cpp:129: warning: comparison between signed and unsigned integer expressions user.cpp:140: warning: comparison between signed and unsigned integer expressions user.cpp:145: warning: comparison between signed and unsigned integer expressions user.cpp:107: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:108: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:109: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:111: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:114: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result