Compilare: user.cpp: In function ‘int main()’: user.cpp:66:21: warning: unused variable ‘b’ [-Wunused-variable] int b = val[y]; ^ user.cpp:72:38: warning: suggest parentheses around comparison in operand of ‘^’ [-Wparentheses] if ( val[x] ^ val[y] == 1 ) { ^ user.cpp:44:28: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(IN, "r", stdin); ^ user.cpp:45:30: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(OUT, "w", stdout); ^ user.cpp:47:31: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(Buf, 1, MaxB, stdin); ^ user.cpp: In function ‘int GetInt()’: user.cpp:24:48: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(Buf, 1, MaxB, stdin), Ptr = 0; ^ user.cpp:28:48: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(Buf, 1, MaxB, stdin), Ptr = 0; ^