Compilare: user.cpp: In function ‘bool litera(char)’: user.cpp:8:18: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] return x>='a'&&x<='z'||x>='A'&&x<='Z'; ^ user.cpp: In function ‘int main()’: user.cpp:13:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("text.in","r",stdin); ^ user.cpp:14:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("text.out","w",stdout); ^