Compilare: user.cpp: In function ‘int main()’: user.cpp:28:55: warning: array subscript has type ‘char’ [-Wchar-subscripts] if( 'a' <= s[i] && s[i] <= 'z' ) lite[s[i]] = 1; ^ user.cpp:20:15: warning: unused variable ‘j’ [-Wunused-variable] int k, i, j; ^ user.cpp: In function ‘void f2(int)’: user.cpp:63:21: warning: array subscript has type ‘char’ [-Wchar-subscripts] coef[q[indi]] += k; ^ user.cpp: In function ‘int main()’: user.cpp:17:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("expresie3.in","r",stdin); ^ user.cpp:18:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("expresie3.out","w",stdout); ^ user.cpp:22:18: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s",s); ^