#include<stdio.h>
int main() {
int first_reaction;
int second_reaction;
    scanf("%d",&first_reaction);
    scanf("%d",&second_reaction);
    if (first_reaction<=0); 
    if(second_reaction<=0);
    printf("Invalid input");
   if else :
    total_mass = frist_reaction + second_reaction
    print(total_mass)
    return 0;
}