#include<bits/stdc++.h>
using namespace std;
#define For(i,a,b) for(int i=(a);i<=(b);i++)
#define Rof(i,a,b) for(int i=(a);i>=(b);i--)
#define ll long long
#define wln putchar('\n')
template<class T1,class T2> void chkmin(T1 &x,T2 y){if(y<x)x=y;}
template<class T1,class T2> void chkmax(T1 &x,T2 y){if(y>x)x=y;}
const int N=5005;
int n,k,a[N],b[N];
int fl[N][N],fr[N][N],f[N][N];
ll sa[N];
int main()
{
    scanf("%d%d",&n,&k);
    For(i,1,n)scanf("%d",a+i),sa[i]=sa[i-1]+a[i];
    For(i,1,k)scanf("%d",b+i);
    For(i,1,k)
    {
        int s=0,p=n;
        fr[i][n+1]=n;
        Rof(j,n,1)
        {
            s+=a[j];
            while(s>b[i])s-=a[p--];
            fr[i][j]=p;
        }
        s=0; p=1;
        fl[i][0]=1;
        For(j,1,n)
        {
            s+=a[j];
            while(s>b[i])s-=a[p++];
            fl[i][j]=p;
        }
    }
    For(i,1,n)f[0][i]=i;
    For(i,0,k-1)
        For(j,1,n)
        {
            chkmax(f[i+1][fl[i+1][j-1]],f[i][j]);
            chkmax(f[i+1][j],fr[i+1][f[i][j]+1]);
        }
    // For(i,1,k)
    //     For(j,1,n)
    //         printf("f[%d][%d]=%d\n",i,j,f[i][j]);
    if(f[k][1]==n)printf("YES\n");
    else printf("NO\n");
}