Compilare: user.cpp: In function ‘void dfs(int, int, int)’: user.cpp:33: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void read()’: user.cpp:41: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:44: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:46: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:49: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘void bfs()’: user.cpp:75: warning: comparison between signed and unsigned integer expressions user.cpp:84: warning: comparison between signed and unsigned integer expressions user.cpp:85: warning: suggest explicit braces to avoid ambiguous ‘else’ user.cpp: In function ‘void back(int)’: user.cpp:107: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void solve()’: user.cpp:121: warning: comparison between signed and unsigned integer expressions