Compilare: user.cpp: In function ‘void solve(int, int, int)’: user.cpp:30:29: warning: suggest parentheses around comparison in operand of ‘^’ [-Wparentheses] if (a[j] ^ a[i] < mini) mini = a[j] ^ a[i]; ^ user.cpp:32:40: warning: suggest parentheses around comparison in operand of ‘^’ [-Wparentheses] if (j < mij && a[j] ^ a[i] < mini) mini = a[j] ^ a[i]; ^ user.cpp:27:13: warning: unused variable ‘val’ [-Wunused-variable] int val = a[i] ^ (1 << bit); ^ user.cpp: In function ‘int main()’: user.cpp:43:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("yamstp.in", "r", stdin); ^ user.cpp:44:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("yamstp.out", "w", stdout); ^ user.cpp:46:17: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d", &T); ^ user.cpp:49:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d", &N); ^ user.cpp:51:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d", &a[i]); ^