#include <stdio.h>

int main(void) {
	int a[100];  
	int soma=2;
	int i=0;
	
	while (soma!=0) {
		scanf("%d", &soma);
		i+=1;
		a[i] = soma;
	
	}
	
	soma = 0;
	while (i!=0) {
		soma = a[i] + soma;
		i+=-1;	
	}
	
	printf("%d", soma);
	return 0;
}