#include<stdio.h>

int main()
{
    int a,b;

    scanf("%d %d", &a, &b);

    for(int i = 10; i < 100;i++)
    {
        int c,d;
        c = i / 10;
        d = i % 10;
        if(a == c + d && (b == c - d || b == d - c))
        {
            printf("%d", i);
            break;
        }
    }

    return 0;
}