bile1.cpp: In function 'bool dfs1(int)': bile1.cpp:16: warning: comparison between signed and unsigned integer expressions bile1.cpp:25: warning: no return statement in function returning non-void bile1.cpp: In function 'bool dfs2(int)': bile1.cpp:31: warning: comparison between signed and unsigned integer expressions bile1.cpp:40: warning: no return statement in function returning non-void bile1.cpp: In function 'bool cleart()': bile1.cpp:48: warning: no return statement in function returning non-void bile1.cpp: In function 'int main()': bile1.cpp:52: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result bile1.cpp:53: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result bile1.cpp:57: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result bile1.cpp:60: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result