#include <stdio.h>
#include <stdbool.h>

int history[1000] = {0};
int nextIndex = 0;

int inHistory(int num) {
    int i = 0;
    for (i = 0; i < nextIndex; i++) {
        if (history[i] == num) {
            return true;
        }
    }
    return false;
}

int main() {
    int input = 0;
    int sum = 0;
    int singleDigit = 0;
    scanf("%d", &input);
    do {
        sum = 0;
        while (input > 0) {
            singleDigit = input % 10;
            sum += singleDigit * singleDigit;
            input /= 10;
        }
        input = sum;
        if (inHistory(sum)) {
            history[nextIndex] = 0;
        }
        else {
            history[nextIndex] = sum;
        }
        nextIndex++;
    }
    while (history[nextIndex-1] > 1);
    printf("%d\n", history[nextIndex-1]);
    return 0;
}