Compilare: user.cpp: In function ‘int eval_func()’: user.cpp:15: warning: array subscript has type ‘char’ user.cpp:29: warning: array subscript has type ‘char’ user.cpp:12: warning: unused variable ‘P’ user.cpp: In function ‘int main()’: user.cpp:119: warning: array subscript has type ‘char’ user.cpp:124: warning: array subscript has type ‘char’ user.cpp:105: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result user.cpp:108: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result