#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <climits>
#include <cassert>
#include <iostream>
#include <iomanip>
#include <string>
#include <stack>
#include <queue>
#include <vector>
#include <map>
#include <set>
#include <algorithm>
#include <numeric>
#include <bitset>

#define all(c) c.begin(), c.end()
#define rall(c) c.rbegin(), c.rend()
#define debug(x) cerr << #x << ": " << x << endl

using namespace std;

typedef long long ll;
typedef pair<ll, ll> Pll;
typedef pair<int, int> Pii;

const ll MOD = 1000000007;
const long double EPS = 1e-10;
const int dyx[4][2] = {
    { 0, 1}, {-1, 0}, {0,-1}, {1, 0}
};

int main() {
    std::ios::sync_with_stdio(0); cin.tie(0);
    int a, b, c, ans = 1<<30;
    cin >> a >> b >> c;


    for(int i=0;i<=a/10;++i) {
        int n = a+b - c;
        if(n <= 0) continue;

        int tmp_ans = min(a, n);
        n -= min(a, n);
        if(n) tmp_ans += min(b, n) * 10;
        ans = min(ans, tmp_ans);

        a -= 10;
        b += 1;
    }

    if(ans == 1<<30) {
        cout << "Impossible\n";
    } else {
        cout << ans << "\n";
    }

    return 0;
}