Compilare: user.cpp: In constructor ‘expresie3::expresie3(char)’: user.cpp:22: warning: array subscript has type ‘char’ user.cpp: In function ‘int main()’: user.cpp:98: warning: comparison between signed and unsigned integer expressions user.cpp:100: warning: array subscript has type ‘char’ user.cpp:102: warning: array subscript has type ‘char’ user.cpp:103: warning: array subscript has type ‘char’ user.cpp:93: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:94: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result