Eroare de compilare: user.cpp: In function ‘long long int calc(char*, unsigned char)’: user.cpp:79: error: invalid conversion from ‘signed char*’ to ‘unsigned char*’ user.cpp:79: error: initializing argument 1 of ‘long long int do_calc(unsigned char*, int, unsigned char)’ user.cpp: In function ‘int main()’: user.cpp:84: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:85: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:87: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result