gropi.cpp: In function 'void bfs(int, int)': gropi.cpp:29: warning: comparison between signed and unsigned integer expressions gropi.cpp: In function 'int main()': gropi.cpp:47: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result gropi.cpp:48: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result gropi.cpp:50: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result gropi.cpp:53: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result