Compilare: user.cpp: In function ‘void input()’: user.cpp:21: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp:25: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘void DFS()’: user.cpp:42: warning: comparison between signed and unsigned integer expressions user.cpp:52: warning: comparison between signed and unsigned integer expressions