croco.cpp: In function 'int BFS()': croco.cpp:20: warning: comparison between signed and unsigned integer expressions croco.cpp: In function 'int main()': croco.cpp:55: warning: comparison between signed and unsigned integer expressions croco.cpp:80: warning: comparison between signed and unsigned integer expressions croco.cpp:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result croco.cpp:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result croco.cpp:40: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result croco.cpp:43: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result