Compilare: user.cpp: In function ‘int main()’: user.cpp:14:10: warning: unused variable ‘a’ [-Wunused-variable] int N, a, b, c; ^ user.cpp:14:13: warning: unused variable ‘b’ [-Wunused-variable] int N, a, b, c; ^ user.cpp:14:16: warning: unused variable ‘c’ [-Wunused-variable] int N, a, b, c; ^ user.cpp:12:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("podm.in", "r", stdin); ^ user.cpp:13:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("podm.out", "w", stdout); ^ user.cpp:16:18: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &N); ^ user.cpp:18:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &v[i]); ^