Compilare: user.cpp: In function ‘int main()’: user.cpp:64:48: warning: unused variable ‘answer’ [-Wunused-variable] int n, m, k, relevant = 0, irrelevant = 0, answer = 1, parity = 0; ^ user.cpp: In function ‘char Advance()’: user.cpp:27:38: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buffer, 1, SIZE, stdin); ^ user.cpp: In function ‘int main()’: user.cpp:62:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("bmat.in", "r", stdin); ^ user.cpp:63:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("bmat.out", "w", stdout); ^ user.cpp:65:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d\n", &n, &m, &k); ^ user.cpp:67:20: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s + 1); ^ /tmp/cc3eMqCy.o: In function `main': user.cpp:(.text.startup+0xa8): warning: the `gets' function is dangerous and should not be used.