#include <cstdio>
#include <algorithm>

const int maxn = 5000;
const int INF = 1000000000;
int n, k;
int w[maxn + 10];
long long suml[maxn + 10];
//long long sumr[maxn + 10];
int s[maxn + 10];
int f[maxn + 10][maxn + 10];

int get_l(int i, int ql){
	int l = ql + 1, r = n;
	while(l != r){
		int mid = (l + r + 1) >> 1;
		if(suml[mid] - suml[ql] <= s[i])
			l = mid;
		else
			r = mid - 1; 
	}
	return l;
}
int get_r(int i, int qr){
	//printf("%d %d\n", i, qr);
	int l = 1, r = qr;
	while(l != r){
		int mid = (l + r) >> 1;
		if(suml[qr - 1] - suml[mid - 1] <= s[i])
			r = mid;
		else
			l = mid + 1; 
	}
	return l;
}

int main(){
	scanf("%d%d", &n, &k);
	for(int i = 1; i <= n; ++i){
		scanf("%d", &w[i]);
		suml[i] = suml[i - 1] + w[i];
	}
	/*for(int i = n; i >= 1; --i){
		sumr[i] = sumr[i + 1] + w[i];
	}*/
	for(int i = 1; i <= k; ++i){
		scanf("%d", &s[i]);
	}
	for(int i = 0; i <= k; ++i){
		for(int j = 0; j <= n; ++j){
			f[i][j] = -INF;
		}
		
	}
	f[0][0] = 0;
	bool flag = false;
	for(int i = 1; i <= k; ++i){
		for(int j = 0; j <= n; ++j){
			f[i][j] = f[i - 1][get_r(i, j + 1) - 1];
			if(f[i - 1][j] >= 0){
				int t = f[i - 1][j] + n + 1 - get_r(i, n + 1 - f[i - 1][j]);
				if(f[i][j] < t)
					f[i][j] = t;
			}
			if(f[i][j] + j >= n - 1){
				flag = true;
				break;
			}
		}
		if(flag)
			break;
	}
	/*for(int i = 1; i <= k; ++i){
		for(int j = 1; j <= n; ++j){
			f[i][j] = f[i - 1][get_r(i, j + 1) - 1];
		}
	}*/
	if(flag)
		printf("Yes");
	else
		printf("No");
	return 0;
}