#include <bits/stdc++.h>
#ifdef LOCAL
#include <debug.h>
#else
#define debug
#endif // LOCAL
using namespace std;
const int INF = 999999;
vector<int> v[500];
vector<int> lant;
vector<int> ciclu;
vector<int> mic;
int vis[500];
int cnt, out;
vector<vector<vector<int>>> dp;
void dfs(int node)
{
// debug("%, ", node);
if(node == 0)
{
out = 1;
return;
}
++cnt;
vis[node] = 1;
for(auto &oth : v[node])
if(!vis[oth])
dfs(oth);
}
signed main()
{
ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
int n, m; cin>>n>>m;
char ch;
for(int i=1; i<=n+1; ++i)
for(int j=1; j<=m; ++j)
{
cin>>ch;
if(ch == '0')
{
int a = (i-1)*(m+1)+j;
int b = i*(m+1)+j;
if(i == 1) a = 0;
if(i == n+1) b = 0;
v[a].push_back(b);
v[b].push_back(a);
}
}
for(int i=1; i<=n; ++i)
for(int j=1; j<=m+1; ++j)
{
cin>>ch;
if(ch == '0')
{
int a = i*(m+1)+j-1;
int b = i*(m+1)+j;
if(j == 1) a = 0;
if(j == m+1) b = 0;
v[a].push_back(b);
v[b].push_back(a);
}
}
mic.push_back(INF);
lant.push_back(INF);
ciclu.push_back(INF);
for(int i=1; i<=n; ++i)
for(int j=1; j<=m; ++j)
{
if(vis[i*(m+1)+j]) continue;
cnt = out = 0;
dfs(i*(m+1)+j);
// debug("\n");
if(cnt == 1 && !out) continue;
if(cnt == 1)
mic.push_back(1);
else if(cnt == 2)
mic.push_back(2);
else if(out)
lant.push_back(cnt);
else
ciclu.push_back(cnt);
}
sort(mic.begin(), mic.end(), greater<int>());
sort(lant.begin(), lant.end(), greater<int>());
sort(ciclu.begin(), ciclu.end(), greater<int>());
int A = mic.size()-1, B = lant.size()-1, C = ciclu.size()-1;
// debug("mic = %\nlant = %\nciclu = %\n", mic, lant, ciclu);
dp.assign(A+5, vector<vector<int>>(B+5, vector<int>(C+5, -INF)));
for(int a=0; a<=A; ++a)
for(int b=0; b<=B; ++b)
for(int c=0; c<=C; ++c)
{
if(!a && !b && !c) dp[a][b][c] = 0;
int oth;
if(a) //mic
{
oth = dp[a-1][b][c] + mic[a];
dp[a][b][c] = max(dp[a][b][c], -oth);
}
if(b) //lant
{
oth = max(dp[a][b-1][c] + lant[b], - dp[a][b-1][c] + lant[b] - 4);
dp[a][b][c] = max(dp[a][b][c], -oth);
}
if(c) //ciclu
{
oth = max(dp[a][b][c-1] + ciclu[c], - dp[a][b][c-1] + ciclu[c] - 8);
dp[a][b][c] = max(dp[a][b][c], -oth);
}
}
cout<<dp[A][B][C];
return 0;
}
