#include <iostream>
using namespace std;

int main() {
    int sum_input = 0;
    int num;
    for(int i = 0; i < 9; i++) {
        cin >> num;
        sum_input += num;
    }

    int missing = 55 - sum_input; // total sum of 1..10 is 55
    cout << missing << endl;

    return 0;
}