Example

Input

6 3
1 0 0 1 0 1
1 3 2


Output

1
#define  _CRT_SECURE_NO_WARNINGS
#pragma comment (linker, "/STACK:526000000")

#include "bits/stdc++.h"

using namespace std;
typedef string::const_iterator State;
#define eps 1e-11L
#define MAX_MOD 1000000007LL
#define GYAKU 500000004LL

#define MOD 998244353LL
#define seg_size 262144*2LL
#define pb push_back
#define mp make_pair
typedef long long ll;
#define REP(a,b) for(long long (a) = 0;(a) < (b);++(a))
#define ALL(x) (x).begin(),(x).end()

unsigned long xor128() {
	static unsigned long x = 123456789, y = 362436069, z = 521288629, w = time(NULL);
	unsigned long t = (x ^ (x << 11));
	x = y; y = z; z = w;
	return (w = (w ^ (w >> 19)) ^ (t ^ (t >> 8)));
}

void init() {
	iostream::sync_with_stdio(false);
	cout << fixed << setprecision(20);
}

#define int ll

void solve() {
	int n, m;
	cin >> n >> m;
	vector<int> inputs;
	REP(i, n) {
		int a;
		cin >> a;
		inputs.push_back(a);
	}
	vector<int> tmp;
	tmp.push_back(0);
	REP(i, m) {
		int a;
		cin >> a;
		tmp.push_back(a);
	}
	int ans = 1e9;
	REP(teas, 2) {
		int now = 0;
		int cnter = 0;
		REP(i, tmp.size()) {
			REP(q, tmp[i]) {
				int cnt = 0;
				REP(j, n) {
					if ((1 << j) & now) {
						continue;
					}
					if (inputs[j] == i % 2) {
						now += (1 << j);
						cnter += cnt;
						break;
					}
					else {
						cnt++;
					}
				}
			}
		}
		if (now == (1 << n) - 1) {
			ans = min(ans, cnter);
		}
		tmp.erase(tmp.begin());
	}
	cout << ans << endl;
}

#undef int
int main() {
	init();
	solve();
}
