include <stdio.h>

int main() {

int n, a, b, c, d, e, s;
scanf("%d", &n);
e = n % 10;
d = n / 10 % 10;
c = n / 100 % 10;
b = n / 1000 % 10;
a = n / 10000 % 10;
s = a + b + c + d + e;
printf("%d", s);

return 0;

}