Compilare: user.cpp: In function ‘int BFS()’: user.cpp:38: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:54: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:55: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:56: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:63: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘int BFS()’: user.cpp:51: warning: control reaches end of non-void function user.cpp: In function ‘int main()’: user.cpp:60: warning: ‘val’ may be used uninitialized in this function