Compilare: user.cpp: In function ‘int main()’: user.cpp:5:12: warning: unused variable ‘i’ [-Wunused-variable] int n, i, sum, x; ^ user.cpp:5:15: warning: unused variable ‘sum’ [-Wunused-variable] int n, i, sum, x; ^ user.cpp:5:20: warning: unused variable ‘x’ [-Wunused-variable] int n, i, sum, x; ^ user.cpp:3:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("taxe.in", "r", stdin); ^ user.cpp:4:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("taxe.out", "w", stdout); ^ user.cpp:6:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^