#include<bits/stdc++.h>
using namespace std;
#define int long long
const int INF = 1e9 + 10;
const int MAXN = 5e3 + 10;
int N,K;
int W[MAXN];
int S[MAXN];
int L[MAXN];
int newL[MAXN];
int R[MAXN];
int newR[MAXN];
int sum[MAXN];

signed main(){
    scanf("%lld %lld",&N,&K);
    for(int i = 1;i <= N; i++) scanf("%lld",&W[i]);
    for(int i = 1;i <= K; i++) scanf("%lld",&S[i]);
    for(int i = 1;i <= N; i++){
        L[i] = R[i] = i;
    }
    for(int i = 1;i <= N; i++){
        sum[i] = sum[i-1] + W[i];
        //cout<<i<<" "<<sum[i]<<"#"<<endl;
    }    
    for(int k = 1;k <= K; k++){
        for(int i = 1;i <= N; i++){
            newL[i] = L[i];
            newR[i] = R[i];
        }
        int pnt = 0;
        for(int i = 1;i <= N; i++){
            while(pnt < N && sum[pnt + 1] - sum[R[i]] <= S[k]){
                pnt++;
                newL[pnt] = min(newL[pnt],i);
            }
            //cout<<i<<" "<<pnt<<"!!!"<<" "<<R[i]<<" "<<sum[pnt+1] - sum[R[i]]<<endl;
            newR[i] = max(newR[i],pnt);
        }
        pnt = N + 1;
        for(int i = N;i >= 1; i--){
            while(pnt >= 2 && sum[L[i] - 1] - sum[pnt - 2] <= S[k]){
                pnt--;
                newR[pnt] = max(newR[pnt],i);
            }
            //cout<<i<<" "<<pnt<<"???"<<endl;
            newL[i] = min(newL[i],pnt);
        }
        for(int i = 1;i <= N; i++){
            L[i] = newL[i];
            R[i] = newR[i];
        }
    }
    // for(int i = 1;i <= N; i++){
    //      cout<<L[i]<<" "<<R[i]<<endl;
    // }
    if(R[1] == N || L[N] == 1){
        printf("Yes\n");
    }
    else printf("No\n");
}