Compilare: user.cpp: In function ‘int fact()’: user.cpp:8: warning: array subscript has type ‘char’ user.cpp:13: warning: array subscript has type ‘char’ user.cpp:13: warning: array subscript has type ‘char’ user.cpp:14: warning: array subscript has type ‘char’ user.cpp: In function ‘int eval()’: user.cpp:21: warning: array subscript has type ‘char’ user.cpp:21: warning: array subscript has type ‘char’ user.cpp:22: warning: array subscript has type ‘char’ user.cpp:26: warning: array subscript has type ‘char’ user.cpp: In function ‘int main()’: user.cpp:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:39: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result /tmp/ccO4A0Qo.o: In function `main': user.cpp:(.text+0x1c3): warning: the `gets' function is dangerous and should not be used.