#include <bits/stdc++.h>
using namespace std;
const int kN = 2e5;
const long long INF = 2e18L;
int a[2 * kN], v[1 + kN];
tuple<int, int, int> intervals[2 * kN];
vector<pair<int, int>> rEnd[1 + kN];
void minSelf(long long &x, long long y)
{
if (y < x)
x = y;
}
struct SegTree
{
int n;
vector<long long> t, lazy;
SegTree(int N) : n(N)
{
int dim = 1;
while (dim < n + 1)
dim *= 2;
dim *= 2;
t.resize(dim);
lazy.resize(dim);
}
void push(int x)
{
if (lazy[x] == 0)
return;
for (int y = 2 * x; y <= 2 * x + 1; ++y)
{
t[y] += lazy[x];
lazy[y] += lazy[x];
}
lazy[x] = 0;
}
void rangeAdd(int x, int lx, int rx, int st, int dr, long long v)
{
if (st <= lx && rx <= dr)
{
t[x] += v;
lazy[x] += v;
return;
}
push(x);
int mid = (lx + rx) / 2;
if (st <= mid)
rangeAdd(x * 2, lx, mid, st, dr, v);
if (mid < dr)
rangeAdd(x * 2 + 1, mid + 1, rx, st, dr, v);
t[x] = min(t[x * 2], t[x * 2 + 1]);
}
void rangeAdd(int st, int dr, long long v)
{
rangeAdd(1, 0, n, st, dr, v);
}
long long query(int x, int lx, int rx, int st, int dr)
{
if (st <= lx && rx <= dr)
return t[x];
push(x);
int mid = (lx + rx) / 2;
long long ans = INF;
if (st <= mid)
minSelf(ans, query(x * 2, lx, mid, st, dr));
if (mid < dr)
minSelf(ans, query(x * 2 + 1, mid + 1, rx, st, dr));
return ans;
}
long long query(int st, int dr)
{
return query(1, 0, n, st, dr);
}
};
long long solve(int n)
{
SegTree t(n);
for (int i = 1; i <= n; ++i)
{
t.rangeAdd(i, i, t.query(0, i - 1));
t.rangeAdd(0, i - 1, v[i]);
for (auto it : rEnd[i])
{
int start, cost;
tie(start, cost) = it;
t.rangeAdd(start, i, cost);
}
}
return t.t[1];
}
int main()
{
int n, m;
scanf("%d %d", &n, &m);
int N = n + m - 1;
for (int i = 1; i <= N; ++i)
scanf("%d", &a[i]);
int cost;
for (int i = 1; i <= N; ++i)
{
scanf("%d", &cost);
int y = min(i - 1, m - 1);
int x = i - 1 - y;
int index = x - y + m;
int len = min(y + 1, n - x);
intervals[i] = {index, len, cost};
}
long long ans = 0;
for (int par = 0; par <= 1; ++par)
{
int p = get<0>(intervals[2 - par]) % 2;
int M = (N + p) / 2;
for (int i = 2 - p; i <= N; i += 2)
v[(i + p) / 2] = a[i];
for (int i = 1; i <= M; ++i)
rEnd[i].clear();
for (int i = 2 - par; i <= N; i += 2)
{
int index, len, cost;
tie(index, len, cost) = intervals[i];
index = (index + 1) / 2;
rEnd[index + len - 1].emplace_back(index, cost);
}
ans += solve(M);
}
printf("%lld\n", ans);
}
