#include<bits/stdc++.h> using namespace std; #define int long long const int N = 10000 + 3; void fun () { int n, k, m; cin >> n >> m >> k; vector<int> a(n + 1), b(m + 1); for (int i = 1; i <= n; i++) cin >> a[i]; for (int i = 1; i <= m; i++) cin >> b[i]; assert(k == 1); vector<int> dp(N); dp[0] = 1; for (int i = 1; i <= m; i++) { for (int j = N - 1; j >= b[i]; j--) { dp[j] |= dp[j - b[i]]; } } int s = 0; for (int i = 1; i <= n; i++) { s += a[i]; } for (int i = s; i < N; i++) { if (dp[i]) { cout << i - s; return; } } cout << "Impossible"; } signed main () { ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); int tt = 1; //cin >> tt; while (tt--) fun(); return 0; }