#include <bits/stdc++.h>
using namespace std;

const vector<int> thres={15, 23, 43, 102};
const vector<int> val={7, 6, 4, 2};

int eval(int e, int a) {
  int d=abs(e-a);
  for (int i=0; i<4; i++)
    if(d<=thres[i]) return val[i];
  return 0;
}

int main() {
  ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
  int n,m; cin>>n>>m;
  vector<vector<int>> dp(n+1,vector<int>(m+1));
  vector<int> e(n), a(m);
  for (int i=0; i<n; i++) cin>>e[i];
  for (int i=0; i<m; i++) cin>>a[i];
  for (int i=0; i<=n; i++) for (int j=0; j<=m; j++) {
    if(i<n) dp[i+1][j]=max(dp[i+1][j],dp[i][j]);
    if(j<m) dp[i][j+1]=max(dp[i][j+1],dp[i][j]);
    if(i<n&&j<m) dp[i+1][j+1]=max(dp[i+1][j+1],dp[i][j]+eval(e[i],a[j]));
  }
  cout<<dp[n][m]<<"\n";
  return 0;
}