#include <bits/stdc++.h>
using namespace std;

int main()
{
	char abbr[10];
	int ans[35];
	int st, len, k = 0, r = 0, first = 0;
	scanf("%s", abbr);
	cin >> st;
	len = strlen(abbr);
	for (int i = 0; i < len; i++)
		{
			int s = (int)(abbr[i]) - 65 + st;
			int tmp[10100], l = 0;
			while (s != 0)
				{
					tmp[l] = s % 10;
					s /= 10;
					k++;
					l++;
				}
			for (int j = l - 1; j >= 0; j--)
				{
					ans[r] = tmp[j];
					r++;
				}
		}//分解简写
	while (k >= 3)
		{
			for (int i = 0; i < k - 1; i++)
				{
					ans[i] = (ans[i] + ans[i + 1]) % 10;
				}
			k--;
		}
	if (ans[0] == 1 && ans[1] == ans[2] == 0)
		cout << "100";
	else
		for (int i = 0; i < 2; i++)
			{
				if (!first && ans[i] == 0)
					continue;
				else
					{
						cout << ans[i];
						first = 1;
					}
			}//输出， 不知道该怎么写
}

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