Compilare: user.cpp: In function ‘int main()’: user.cpp:23:9: warning: unused variable ‘j’ [-Wunused-variable] int i, j; ^ user.cpp: In function ‘void Read()’: user.cpp:56:6: warning: unused variable ‘i’ [-Wunused-variable] int i; ^ user.cpp: In function ‘int main()’: user.cpp:20:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("deque.in", "r", stdin); ^ user.cpp:21:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("deque.out", "w", stdout); ^ user.cpp: In function ‘void Next()’: user.cpp:77:32: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] std::fread(c, 1, MAXC, stdin); ^