Compilare: user.cpp: In function ‘int lexicografic(int, int)’: user.cpp:10:37: warning: operation on ‘j’ may be undefined [-Wsequence-point] { if(s[j++]>s[j] && s[j++]<s[j]); else return -1; ^ user.cpp: In function ‘int main()’: user.cpp:18:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("charlie.in","r",stdin); ^ user.cpp:19:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("charlie.out","w",stdout); ^