#include <bits/stdc++.h>
using namespace std;
template<typename T>
void out(T x) { cout << x << endl; exit(0); }
#define watch(x) cout << (#x) << " is " << (x) << endl
using ll = long long;
const int maxn = 1e6 + 5;
int n;
vector<int> a;
set<int> digits(int x) {
set<int> res;
while (x) {
res.insert(x%10);
x/=10;
}
return res;
}
bool test(int x) {
for (int i=0; i<n; i++) {
int cur=x+i;
bool ok = false;
while (cur) {
if (a[i]==cur%10) {
ok=true; break;
}
cur/=10;
}
if (!ok) {
return false;
}
}
return true;
}
int brute(vector<int> a) {
for (int i=1; ; i++) {
if (test(i)) return i;
}
assert(false);
return -1;
}
int solve1(int d) {
if (1<=d && d<=8) {
int ten = 1;
while (ten < n) ten *= 10;
return d*ten;
} else if (d==0) {
int ans = 10;
int hit = 1;
while (hit<n) {
ans *= 10;
hit *= 10;
hit += 1;
}
return ans;
} else if (d==9) {
for (int len=1;;len++) {
string lo;
for (int i=0; i<len-1; i++) lo += '8';
lo += '9';
string hi(len,'9');
int have = stoi(hi)-stoi(lo)+1;
if (have >= n) {
return stoi(lo);
}
}
}
assert(false);
return -1;
}
int main() {
ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
cin>>n;
a.resize(n);
set<int> st;
for (int i=0; i<n; i++) {
cin>>a[i];
st.insert(a[i]);
}
if ((int)st.size() == 1) {
int res = solve1(a[0]);
out(res);
}
int bru = brute(a);
out(bru);
return 0;
}
