Compilare: user.cpp: In function ‘void read()’: user.cpp:9: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:10: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:11: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:13: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘void dfs(int, int)’: user.cpp:26: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void rmq()’: user.cpp:39: warning: name lookup of ‘i’ changed user.cpp:6: warning: matches this ‘i’ under ISO standard rules user.cpp:33: warning: matches this ‘i’ under old rules user.cpp: In function ‘void query()’: user.cpp:50: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result