#line 1 "main.cpp"
//#pragma GCC target("avx")
//#pragma GCC optimize("O3")
//#pragma GCC optimize("unroll-loops")
#include<bits/stdc++.h>
#ifdef LOCAL
#include <debug.hpp>
#define debug(...) debug_print::multi_print(#__VA_ARGS__, __VA_ARGS__)
#else
#define debug(...) (static_cast<void>(0))
#endif
using namespace std;
using ll = long long;
using ld = long double;
using pll = pair<ll, ll>;
using pii = pair<int, int>;
using vi = vector<int>;
using vvi = vector<vi>;
using vvvi = vector<vvi>;
using vl = vector<ll>;
using vvl = vector<vl>;
using vvvl = vector<vvl>;
using vpii = vector<pii>;
using vpll = vector<pll>;
using vs = vector<string>;
template<class T> using pq = priority_queue<T, vector<T>, greater<T>>;
#define overload4(_1, _2, _3, _4, name, ...) name
#define overload3(a,b,c,name,...) name
#define rep1(n) for (ll UNUSED_NUMBER = 0; UNUSED_NUMBER < (n); ++UNUSED_NUMBER)
#define rep2(i, n) for (ll i = 0; i < (n); ++i)
#define rep3(i, a, b) for (ll i = (a); i < (b); ++i)
#define rep4(i, a, b, c) for (ll i = (a); i < (b); i += (c))
#define rep(...) overload4(__VA_ARGS__, rep4, rep3, rep2, rep1)(__VA_ARGS__)
#define rrep1(n) for(ll i = (n) - 1;i >= 0;i--)
#define rrep2(i,n) for(ll i = (n) - 1;i >= 0;i--)
#define rrep3(i,a,b) for(ll i = (b) - 1;i >= (a);i--)
#define rrep4(i,a,b,c) for(ll i = (a) + ((b)-(a)-1) / (c) * (c);i >= (a);i -= c)
#define rrep(...) overload4(__VA_ARGS__, rrep4, rrep3, rrep2, rrep1)(__VA_ARGS__)
#define all1(i) begin(i) , end(i)
#define all2(i,a) begin(i) , begin(i) + a
#define all3(i,a,b) begin(i) + a , begin(i) + b
#define all(...) overload3(__VA_ARGS__, all3, all2, all1)(__VA_ARGS__)
#define sum(...) accumulate(all(__VA_ARGS__),0LL)
template<class T> bool chmin(T &a, const T &b){ if(a > b){ a = b; return 1; } else return 0; }
template<class T> bool chmax(T &a, const T &b){ if(a < b){ a = b; return 1; } else return 0; }
template<class T> auto min(const T& a){return *min_element(all(a));}
template<class T> auto max(const T& a){return *max_element(all(a));}
template<class... Ts> void in(Ts&... t);
#define INT(...) int __VA_ARGS__; in(__VA_ARGS__)
#define LL(...) ll __VA_ARGS__; in(__VA_ARGS__)
#define STR(...) string __VA_ARGS__; in(__VA_ARGS__)
#define CHR(...) char __VA_ARGS__; in(__VA_ARGS__)
#define DBL(...) double __VA_ARGS__; in(__VA_ARGS__)
#define LD(...) ld __VA_ARGS__; in(__VA_ARGS__)
#define VEC(type, name, size) vector<type> name(size); in(name)
#define VV(type, name, h, w) vector<vector<type>> name(h, vector<type>(w)); in(name)
ll intpow(ll a, ll b){ ll ans = 1; while(b){if(b & 1) ans *= a; a *= a; b /= 2;} return ans;}
ll modpow(ll a, ll b, ll p){ ll ans = 1; a %= p;if(a < 0) a += p;while(b){ if(b & 1) (ans *= a) %= p; (a *= a) %= p; b /= 2; } return ans; }
ll GCD(ll a,ll b) { if(a == 0 || b == 0) return 0; if(a % b == 0) return b; else return GCD(b,a%b);}
ll LCM(ll a,ll b) { if(a == 0) return b; if(b == 0) return a;return a / GCD(a,b) * b;}
namespace IO{
#define VOID(a) decltype(void(a))
struct setting{ setting(){cin.tie(nullptr); ios::sync_with_stdio(false);fixed(cout); cout.precision(12);}} setting;
template<int I> struct P : P<I-1>{};
template<> struct P<0>{};
template<class T> void i(T& t){ i(t, P<3>{}); }
void i(vector<bool>::reference t, P<3>){ int a; i(a); t = a; }
template<class T> auto i(T& t, P<2>) -> VOID(cin >> t){ cin >> t; }
template<class T> auto i(T& t, P<1>) -> VOID(begin(t)){ for(auto&& x : t) i(x); }
template<class T, size_t... idx> void ituple(T& t, index_sequence<idx...>){
    in(get<idx>(t)...);}
template<class T> auto i(T& t, P<0>) -> VOID(tuple_size<T>{}){
    ituple(t, make_index_sequence<tuple_size<T>::value>{});}
#undef VOID
}
#define unpack(a) (void)initializer_list<int>{(a, 0)...}
template<class... Ts> void in(Ts&... t){ unpack(IO :: i(t)); }
#undef unpack
static const double PI = 3.1415926535897932;
template <class F> struct REC {
    F f;
    REC(F &&f_) : f(forward<F>(f_)) {}
    template <class... Args> auto operator()(Args &&...args) const { return f(*this, forward<Args>(args)...); }};
//constexpr int mod = 1000000007;
constexpr int mod = 998244353;

#line 2 "library/string/z_algorithm.hpp"
template<typename Container>
vector<int> z_algorithm(Container s) {
    int n = s.size();
    if(n == 0) return {};
    vector<int> a(n);
    a[0] = n;
    int i = 1, j = 0;
    while (i < n) {
        while (i + j < n && s[j] == s[i + j]) ++j;
        a[i] = j;
        if (j == 0) {
            ++i;
            continue;
        }
        int k = 1;
        while (i + k < n && k + a[k] < j) a[i + k] = a[k], ++k;
        i += k;
        j -= k;
    }
    return a;
}
#line 2 "library/data-structure/Dynamic-Li-Chao-Tree.hpp"
template<typename T,T x_low,T x_high,T id>
struct DynamicLiChaoTree {
    struct Line {
        T a, b;
        Line(T a, T b) : a(a), b(b) {}
        inline T get(T x) const {return a * x + b;}
    };
    struct Node {
        Line x;
        Node *l, *r;
        Node(const Line &x) : x{x}, l{nullptr}, r{nullptr} {}
    };
    Node *root;
    DynamicLiChaoTree() : root{nullptr} {}
    Node *add_line(Node *t, Line &x, const T &l, const T &r, const T &x_l, const T &x_r) {
        if(!t) return new Node(x);
        T t_l = t->x.get(l), t_r = t->x.get(r);
        if(t_l <= x_l && t_r <= x_r) return t; 
        else if(t_l >= x_l && t_r >= x_r) {
            t->x = x;
            return t;
        } 
        else {
            T m = (l + r) / 2;
            if(m == r) --m;
            T t_m = t->x.get(m), x_m = x.get(m);
            if(t_m > x_m) {
                swap(t->x, x);
                if(x_l >= t_l) t->l = add_line(t->l, x, l, m, t_l, t_m);
                else t->r = add_line(t->r, x, m + 1, r, t_m + x.a, t_r);
            } 
            else {
                if(t_l >= x_l) t->l = add_line(t->l, x, l, m, x_l, x_m);
                else t->r = add_line(t->r, x, m + 1, r, x_m + x.a, x_r);
            }
            return t;
        }
    }
    void add_line(const T &a, const T &b) {
        Line x(a, b);
        root = add_line(root, x, x_low, x_high, x.get(x_low), x.get(x_high));
    }
    Node *add_segment(Node *t, Line &x, const T &a, const T &b, const T &l, const T &r, const T &x_l, const T &x_r) {
        if(r < a || b < l) return t;
        if(a <= l && r <= b) {
            Line y{x};
            return add_line(t, y, l, r, x_l, x_r);
        }
        if(t) {
            T t_l = t->x.get(l), t_r = t->x.get(r);
            if(t_l <= x_l && t_r <= x_r) return t;
        } 
        else t = new Node(Line(0, id));
        T m = (l + r) / 2;
        if(m == r) --m;
        T x_m = x.get(m);
        t->l = add_segment(t->l, x, a, b, l, m, x_l, x_m);
        t->r = add_segment(t->r, x, a, b, m + 1, r, x_m + x.a, x_r);
        return t;
    }
    void add_segment(const T &l, const T &r, const T &a, const T &b) {
        Line x(a, b);
        root = add_segment(root, x, l, r - 1, x_low, x_high, x.get(x_low), x.get(x_high));
    }
    T query(const Node *t, const T &l, const T &r, const T &x) const {
        if(!t) return id;
        if(l == r) return t->x.get(x);
        T m = (l + r) / 2;
        if(m == r) --m;
        if(x <= m) return min(t->x.get(x), query(t->l, l, m, x));
        else return min(t->x.get(x), query(t->r, m + 1, r, x));
    }
    T query(const T &x) const {
        return query(root, x_low, x_high, x);
    }
};
#line 88 "main.cpp"
int main() {
    INT(n,m);
    VEC(int,a,n);
    VEC(int,b,m);
    VEC(int,c,m);
    vi tmp = a;
    tmp.emplace_back(-1);
    rep(i,m) tmp.emplace_back(b[i]);
    auto ret = z_algorithm(tmp);
    vi R(m);
    rep(i,n+1,ret.size()) {
        R[i-(n+1)] = ret[i];
    }
    static const ll inf = 1e18;
    DynamicLiChaoTree<ll,0,200200,(ll)inf> cht;
    vl dp(m+1,inf);
    dp[0] = 0;
    rep(i,m) {
        if(dp[i] != inf) cht.add_segment(i+1,i+R[i]+1,c[i],dp[i]-c[i]*i);
        dp[i+1] = cht.query(i+1);
    }
    if(dp.back() == inf) cout << -1 << '\n';
    else cout << dp.back() << '\n';
}