#include <bits/stdc++.h>
 
using namespace std;
 
 
//repetition
#define FOR(i, a, b) for (int i = (a); i < (b); ++i)
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define euc_dis(x, y) sqrt(x*x + y*y)
 
#define pb push_back
#define mp make_pair
#define INF 999999999
#define MOD 1000000007
#define sp ' '
#define ALL(a)  (a).begin(),(a).end()
#define RALL(a) (a).rbegin(), (a).rend()
 
//typedef
typedef long long ll;
typedef pair<int, int> pint;
typedef map<int, int> mint;
typedef vector<int> vint;
typedef vector<char> vch;
typedef vector<long long> vll;
typedef vector<string> vstr;
 
 
int mod(int a, int b){return (a%b+b)%b;}
int gcd(int a,int b){return b?gcd(b,a%b):a;}
void Yes(){cout << "Yes" << endl;}
void No(){cout << "No" << endl;}
void Judge(bool b){b?Yes():No();}
void YES(){cout << "YES" << endl;}
void NO(){cout << "NO" << endl;}
void JUDGE(bool b){b?YES():NO();}
ll powMod(ll a, ll b){ll ans=1; rep(i, b){ans=ans*a%MOD;} return ans;}
 
template<typename T>
void ppp(T n){cout << n << endl;}
template<typename T>
void dpp(T n){cerr << n << endl;}
 
const int dx[4]={1,0,-1,0};
const int dy[4]={0,1,0,-1};
const int ddx[8] = {1,0,-1,0,1,-1,-1,1};
const int ddy[8] = {0,1,0,-1,1,1,-1,-1};
 
 
 
 
template < typename T > std::string to_string( const T& n )
{
    std::ostringstream stm ;
    stm << n ;
    return stm.str() ;
}
 
 
vector<string> split(const string &str, char sep)
{
    vector<string> v;
    stringstream ss(str);
    string buffer;
    while( getline(ss, buffer, sep) ) {
        v.pb(buffer);
    }
    return v;
}
 
 
 
 
int main(){
 
    cin.tie(0);
    ios::sync_with_stdio(false);

    ll a, b;
    cin >> a >> b;

    if(a*b%10 == a*b or a%10 == 0 and b%10 == 0){
        ppp(a*b/10);
        return 0;
    }
    else{
        if(abs(a*b) <= 99999999){
            ppp(a*b);
            return 0;
        }
        else{
            ppp("E");
            return 0;
        }
    }
 
    
}