Compilare: user.cpp: In function ‘int main()’: user.cpp:24:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i = 2; i < v.size(); i++) { ^ user.cpp:10:12: warning: unused variable ‘j’ [-Wunused-variable] int i, j, x; ^ user.cpp:11:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("emax.in", "r", stdin); ^ user.cpp:12:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("emax.out", "w", stdout); ^ user.cpp:13:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &N); ^ user.cpp:15:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &x); ^