How to ignore some input when I don't need it for the computation in C++?

Question

The code below just needs to output the sum = unit1 * price1 + unit2 * price2 ; I don't need the code1,code2 of goods. I don't know how to skip them in my program? I did not know - so i had to read them and store them in code1, code2.How to ignore them?

I tried to do cin >> >> unit1 >> price1 ; but it says "error". I can't just do it!

#include <iostream>
using namespace std ;

 int main(){

     int code1 ;
     int code2 ;
     int unit1 ;
     int unit2 ;
     float price1 ;
     float price2 ;

     cin >> code1 >> unit1 >>price1 ;
     cin >> code2 >> unit2 >>price2 ;


     float result = unit1 * price1 + unit2*price2 ;

     printf("to pay: R$ %.2f\n" ,result ) ;

     }

Answer 1

If you only need the last 2 integers, define only two integers, a1 and a2.

int a1, a2;
scanf("%d%d%d", &a1, &a1, &a2);