Compilare: user.cpp: In function ‘void input()’: user.cpp:20: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp:24: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘void DFS()’: user.cpp:41: warning: comparison between signed and unsigned integer expressions user.cpp:50: warning: comparison between signed and unsigned integer expressions