#include <iostream>
#include <fstream>
using namespace std;

int main(void)
{
    int n, n1, m, m1;
    int a[50];
    int a1[50];
    ifstream in("input.txt");
    in >> n;
    cin >> n1;
    for (int i =0; i<n;i++)
    {
    in >> a[i];
    }
    for (int i =0; i<n1;i++)
    {
    cin >> a[i];
    }
    for(int i=1;i<n;i++)
    {
    m += (a[i]*a[i+1]/24)*i;
    }
    for(int i=1;i<n1-1;i++)
    {
    m1 += (a1[i]*a1[i+1]/24)*i;
    }
    ofstream out("output.txt");
    out << m1;
}