#include <bits/stdc++.h>
using namespace std;

const int N = 5100;

int n, k;
int w[N], s[N], dp[N][N];
int goR[N][N], goL[N][N];

int main() {
    ios_base::sync_with_stdio(0), cin.tie(0);

    cin >> n >> k;
    for (int i = 1; i <= n; ++i) {
        cin >> w[i];
    }
    for (int i = 1; i <= k; ++i) {
        cin >> s[i];
    }
    reverse(s + 1, s + k + 1);
    vector<pair<int, int>> v;
    for (int i = 1; i <= k; ++i) {
        v.push_back({s[i], i});
    }
    sort(v.begin(), v.end());
    for (int i = 1; i <= n; ++i) {
        int pos = i - 1;
        long long W = 0;
        for (auto [x, j] : v) {
            while (pos + 1 <= n && W + w[pos + 1] <= x) {
                pos++;
                W += w[pos];
            }
            goR[i][j] = pos;
        }
    }
    for (int i = 1; i <= n; ++i) {
        int pos = i + 1;
        long long W = 0;
        for (auto [x, j] : v) {
            while (pos - 1 >= 1 && W + w[pos - 1] <= x) {
                pos--;
                W += w[pos];
            }
            goL[i][j] = pos;
        }
    }

    for (int i = 1; i <= k + 1; ++i) {
        for (int j = 1; j <= n + 1; ++j) {
            dp[i][j] = 1e9;
        }
    }
    dp[1][1] = n;
    for (int i = 1; i <= k; ++i) {
        for (int j = 1; j <= n; ++j) {
            if (dp[i][j] == 1e9) continue;
            dp[i + 1][goR[j][i] + 1] = min(dp[i + 1][goR[j][i] + 1], dp[i][j]);
            dp[i + 1][j] = min(dp[i + 1][j], goL[dp[i][j]][i] - 1);
        }
    }
    for (int i = 1; i <= n; ++i) {
        if (dp[k + 1][i] <= i) {
            cout << "Yes\n";
            return 0;
        }
    }
    cout << "No\n";
    return 0;
}