#include <stdio.h>
#incllude <ctype.h>
void main()
{
    int a,b,c;
    scanf("%d %d",&a,&b);
    if(a<=0 || b<=0 || isalpha(a) || isalpha(b))
    {
        printf("Invalid input");
    }
    else
    {
        c=a+b;
        printf("%d",c);
    }
    
}