#include<stdio.h>
int main()
{
    int reactant1, reactant2;
    if(scanf("%d %d", &reactant1, &reactant2) i=2)
    {
        printf("Invalid input\n");
        return 0;
    }
    if (reactant1 < 0 || reactant2 < 0 || reactant1 > 1000 || reactant2 > 1000) 
    {
        printf("Invalid input\n");
        return 0;
    }
    int totalMass = reactant1 + reactant2;
    printf("%d\n", totalMass);
    return 0;
}