#include <bits/stdc++.h>

using namespace std;

const int N = 5005;

int n, k, dp[N][N], a[N];
long long sum[N], can[N];

int main() {
  cin.tie(0)->sync_with_stdio(0);
  cin >> n >> k;
  for (int i = 1; i <= n; i++) {
    cin >> a[i]; sum[i] = sum[i - 1] + a[i];
  }
  for (int i = 1; i <= k; i++)
    cin >> can[i];
  memset(dp, 0x3f, sizeof dp);
  a[0] = a[n + 1] = dp[0][0];
  for (int i = n; i > 0; i--) {
    dp[i][i] = 0;
    for (int j = i; j <= n; j++) {
      int v = dp[i][j] + 1;
      while (v <= k && can[v] < min(a[i - 1], a[j + 1])) v++;
      if (v > k) break;
      int l = 0, r = i - 1;
      while (l < r) {
        int m = (l + r) / 2;
        if (sum[i - 1] - sum[m] <= can[v])
          r = m;
        else l = m + 1;
      }
      dp[r + 1][j] = min(dp[r + 1][j], v);
      l = j; r = n;
      while (l < r) {
        int m = (l + r + 1) / 2;
        if (sum[m] - sum[j] <= can[v])
          l = m;
        else r = m - 1;
      }
      dp[i][l] = min(dp[i][l], v);
    }
  }
  cout << (dp[1][n] <= k ? "Yes" : "No");
}