Compilare: user.cpp: In function ‘int main()’: user.cpp:7:15: warning: unused variable ‘i’ [-Wunused-variable] int t, n, k, i; ^ user.cpp:5:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("mere.in", "r", stdin); ^ user.cpp:6:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("mere.out", "w", stdout); ^