#include<stdio.h>
int main()
{
       int first reactant,second_reactant;
    if ( scanf("%d",&first_reactant)!=1 ||
    scanf("%d",&second_reactant) !=1) {
        printf("Invalid input");
        return 0;
    }
    if(first_reactant<0  || second_reactant<0) {
        printf("Invalid input");
        return 0;
    }
    int total_mass=first_reactant + second_reactant;
    printf("%d",total_mass);
    
    return 0;
}