#pragma GCC optimize("O5,unroll-loops,inline,fast-math") #pragma GCC target("avx2,bmi,bmi2,popcnt,lzcnt") #include <bits/stdc++.h> #define exoworldgd cin.tie(0)->sync_with_stdio(0), cout.tie(0) #define int long long using namespace std; const int N=305,M=90005; int n,m,k,a[N],b[N],need=0,res=M; bitset<M> small,big[N]; signed main(void) { exoworldgd; cin >> n >> m >> k; for (int i=0; i<n; i++) cin >> a[i]; for (int i=0; i<m; i++) cin >> b[i]; sort(b,b+m); for (int i=0; i<n; i++) { if (a[i]<k) return cout << "Impossible\n",0; need+=a[i]-k; } small[0]=1; for (int i=0; i<m && b[i]<n; i++) small|=small<<b[i]; big[0][0]=1; for (int i=m-1; i+1 && b[i]>=n; i--) { for (int c=min(m,k); c; c--) { bitset<M> add=big[c-1]<<(b[i]-n); big[c]|=add|(big[c]<<b[i]); } } for (int c=k; c+1; c--) { for (int x=M-1,y=0; x+1; x--) { while (x+1 && !big[c][x]) x--; while (x+1 && y<M && (!small[y] || x+y<need)) y++; if (x+1 && y<M) res=min(res,x+y-need); } small>>=n; } if (res==M) cout << "Impossible\n"; else cout << res << '\n'; }