Compilare: user.cpp: In function ‘int main()’: user.cpp:21:21: warning: variable ‘st’ set but not used [-Wunused-but-set-variable] int n, l, u, i, st, dr, a, frecv, ok; ^ user.cpp:22:15: warning: variable ‘nr’ set but not used [-Wunused-but-set-variable] long long nr = 0; ^ user.cpp:19:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("secv5.in", "r", stdin); ^ user.cpp:20:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("secv5.out", "w", stdout); ^ user.cpp:23:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &n, &l, &u); ^ user.cpp:25:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &v[i]); ^