Compilare: main.cpp: In function 'int main()': main.cpp:98:23: warning: unused variable 'last' [-Wunused-variable] int cnt=0,last=0; ^~~~ main.cpp: In member function 'char input_parser::next()': main.cpp:41:65: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(this->buffer,1,max_load,this->fin),this->pos=0; ^