// yukicoder: No.722 100×100=1000
// 2019.4.21 bal4u

#include <stdio.h>

int man(int a)
{
	int f;
	if (a < 0) a = -a;
	if (a < 100) return 0;
	f = 0; while (a) {
		if (a % 10) f++;
		a /= 10;
		if (f > 1) return 0;
	}
	return 1;
}

int main()
{
	int A, B;
	long long ans;

	scanf("%d%d", &A, &B), ans = (long long)A * B;
	if (man(A) && man(B)) printf("%lld\n", ans/10);
	else {
		if (ans >= -99999999 && ans <= 99999999) printf("%lld\n", ans);
		else puts("E");
	}
	return 0;
}