Compilare: user.cpp: In function ‘void r(int&)’: user.cpp:19:9: warning: variable ‘semn’ set but not used [-Wunused-but-set-variable] int semn = 1; ^ user.cpp: In function ‘char next()’: user.cpp:14:16: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] pos = 0; ^ user.cpp: In function ‘int main()’: user.cpp:22:22: warning: ‘ch’ is used uninitialized in this function [-Wuninitialized] while(!isdigit(ch) && ch != '-') ^ user.cpp:20:10: note: ‘ch’ was declared here char ch; ^ user.cpp:39:26: warning: ‘ch’ may be used uninitialized in this function [-Wmaybe-uninitialized] while(!isalpha(ch)) ^