#include<iostream>
#include<cstdio>
#define N 5000
using namespace std;
const int inf=(int)(1e9);
int read()
{
	char c=0;
	int sum=0;
	while (c<'0'||c>'9') c=getchar();
	while ('0'<=c&&c<='9') sum=sum*10+c-'0',c=getchar();
	return sum;
}
int n,k,lg[N+1],w[N+1],s[N+1],dp[N+1][N+1],maxn[N+1][N+1];
long long st[N+1];
int main()
{
	int ps,d;
	for (int i=2;i<=N;++i) lg[i]=lg[i>>1]+1;
	n=read(),k=read();
	for (int i=1;i<=n;++i) w[i]=read(),st[i]=st[i-1]+w[i];
	for (int i=1;i<=k;++i) s[i]=read();
	for (int i=1;i<=k;++i)
	{
		maxn[i][i]=s[i];
		for (int j=i+1;j<=k;++j) maxn[i][j]=max(maxn[i][j-1],s[j]);
	}
	for (int i=n;i>=1;--i)
		for (int j=i;j<=n;++j)
			dp[i][j]=(i==j)?0:inf;
	for (int i=n;i>=1;--i)
		for (int j=i;j<=n;++j)
			if (dp[i][j]<=k-1)
			{
				if (j!=n)
				{
					d=dp[i][j];
					for (int t=lg[k-dp[i][j]+1];t>=0;--t)
						if (d+(1<<t)<=k&&maxn[dp[i][j]+1][d+(1<<t)]<w[j+1])
							d+=(1<<t);
					d++;
					if (d<=k)
					{
						ps=j;
						for (int t=lg[n-j+1];t>=0;--t)
							if (ps+(1<<t)<=n&&st[ps+(1<<t)]-st[j]<=s[d])
								ps+=(1<<t);
						dp[i][ps]=min(dp[i][ps],d);
					}
				}
				if (i!=1)
				{
					d=dp[i][j];
					for (int t=lg[k-dp[i][j]+1];t>=0;--t)
						if (d+(1<<t)<=k&&maxn[dp[i][j]+1][d+(1<<t)]<w[i-1])
							d+=(1<<t);
					d++;
					if (d<=k)
					{
						ps=i;
						for (int t=lg[i];t>=0;--t)
							if (ps-(1<<t)>=1&&st[i-1]-st[ps-(1<<t)-1]<=s[d])
								ps-=(1<<t);
						dp[ps][j]=min(dp[ps][j],d);
					}
				}
			}
	puts(dp[1][n]!=inf?"Yes":"No");
	return 0;
}