//#include <bits/stdc++.h>
#include<iostream>
#include <iosfwd>
#include<limits.h>
#include <sstream>
#include <iomanip>
#include <iterator>
#include <algorithm>
#include <limits>
#include<stdio.h>
#include <queue>
#include <stack>
#include <math.h>
#include<string.h>
#include <unordered_map>
#include <map>
#include <unordered_set>
#include <set>
#include<vector>
#include <chrono>
#include <random>
#include <bitset>
using namespace std;
#define fr(i,j,n)   for(lli i=j;i<(n);++i)
#define bk(i,j,n)   for(lli i=j;i>=n&&j>=n;--i)
#define pb push_back
#define F first
#define S second
#define endl "\n"
#define mem(p,v) memset(p,v,sizeof(p))
#define present(c,x)    ((c).find(x) != (c).end())
#define run ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0)
#define ordered_set tree<lli, null_type,less<lli>, rb_tree_tag,tree_order_statistics_node_update>
#define debug1(x) cout<<#x<<" "<<x<<endl;
#define debug2(x,y) cout<<#x<<" "<<x<<" "<<#y<<" "<<y<<endl;
#define debug3(x,y,z) cout<<#x<<" "<<x<<" "<<#y<<" "<<y<<" "<<#z<<" "<<z<<endl;
#define debug4(x,y,z,a) cout<<#x<<" "<<x<<" "<<#y<<" "<<y<<" "<<#z<<" "<<z<<" "<<#a<<" "<<a<<endl;
#define ub upper_bound
#define lb lower_bound
typedef long long int lli;
typedef unsigned long long ull;
typedef vector<int> vi;
typedef pair<int,int> pi;
typedef vector<lli> vl;
typedef pair<lli,lli> pl;
inline lli max(lli a,lli b){ return a>b?a:b;}
inline lli min(lli a,lli b){ return a<b?a:b;}
const long long inf = 1e18;
const lli MOD =998244353 ;
void show(vector<lli> v){fr(i,0,v.size())cout<<v[i]<<" ";cout<<endl;}
void show(vector<int> v){fr(i,0,v.size())cout<<v[i]<<" ";cout<<endl;}
void show(int a[], int arraysize){for (int i = 0; i < arraysize; ++i)cout << a[i] << " ";cout<<endl;}
void show(lli a[], lli arraysize){for (lli i = 0; i < arraysize; ++i)cout << a[i] << " ";cout<<endl;}
void show(bool a[], lli arraysize){for (lli i = 0; i < arraysize; ++i)cout << a[i] << " ";cout<<endl;}
void show(set<int> s){for (auto it = s.begin(); it != s.end(); it++){cout << *it << " ";}cout<<endl;}
void show(map<lli,lli> mp){for (auto it = mp.begin(); it != mp.end(); it++){cout << it->first << " "<<it->second<<endl;}cout<<endl;}
//Pair hashing is done using std::map ;
lli modpow(lli x,lli n){lli res=1;while(n>0){if(n&1) res=((res%MOD)*(x%MOD))%MOD;x=((x%MOD)*(x%MOD))%MOD;n>>=1;}return res;}
lli power(lli x, lli n){lli res=1;while(n>0){if(n&1) res=res*x;x=x*x;n>>=1;}return res;}

/////// ------ Main code starts here ------ /////
void solve()
{
    lli R,G,B;
    cin>>R>>G>>B;
    vl r(R),g(G),b(B);
    fr(i,0,R)
    {
        cin>>r[i];
    }
    fr(i,0,G)
    {
        cin>>g[i];
    }
    fr(i,0,B)
    {
        cin>>b[i];
    }
    sort(r.begin(),r.end(),greater<int>());
    sort(g.begin(),g.end(),greater<int>());
    sort(b.begin(),b.end(),greater<int>());
    lli dp[R+1][G+1][B+1];
    for(int i=0;i<R+1;++i)
    {
        for(int j=0;j<G+1;++j)
        {
            for(int k=0;k<B+1;++k)
            {
                dp[i][j][k]=0;
                if((i==0&&j==0)||(k==0&&j==0)||(i==0&&k==0))
                    continue;
                if(j>0&&k>0)
                {
                    dp[i][j][k]=max(dp[i][j][k],dp[i][j-1][k-1]+g[j-1]*b[k-1]);
                }
                if(i>0&&k>0)
                {
                    dp[i][j][k]=max(dp[i][j][k],dp[i-1][j][k-1]+r[i-1]*b[k-1]);
                }
                if(i>0&&j>0)
                {
                    dp[i][j][k]=max(dp[i][j][k],dp[i-1][j-1][k]+r[i-1]*g[j-1]);
                }
            }
        }
    }
    cout<<dp[R][G][B]<<endl;
}
int main()
{
    run;cout<<fixed<<setprecision(12);
    int t;
    t=1;
    while(t){solve();t--;}
    return 0;
}