#include <bits/stdc++.h>
#define PI 3.14159265359
using namespace std;
const int64_t MOD = 1e9 + 7;

int check(int64_t n) {
	int cnt = 0;
	int cz = 0;

	while (n) {
		int a = n % 10;
		cnt++;
		if (!a) cz++;

		n /= 10;
	}

	if (cz+1==cnt) {
		return 1;
	}
	else {
		return 0;
	}
}

int main() {
	int64_t A, B;
	cin >> A >> B;

	string a, b;
	a = to_string(A);
	b = to_string(B);
	int64_t ans = A * B;

	if (check(A) && check(B)) {
		ans /= 10;
	}
	else {
		if (ans / 100000000 != 0) {
			cout << "E" << endl;
			return 0;
		}
	}

	cout << ans << endl;
}