#include<bits/stdc++.h>
#define pb push_back
#define mp make_pair
#define int long long
#define vi vector<int>
#define vvi vector<vector<int>>
#define pii pair<int, int>
#define vpii vector<pair<int, int>>
#define vc vector<char>
#define vb vector<bool>
#define mii map<int,int>
#define f0r(i,n) for(int i=0;i<n;i++)
#define FOR(i,k,n) for(int i=k;i<n;i++)
#define all(v) (v).begin(),(v).end()
#define rall(v) (v).rbegin(),(v).rend()
#define in(a) int a; cin>>a
#define in2(a,b) int a,b; cin>>a>>b
#define in3(a,b,c) int a,b,c; cin>>a>>b>>c
#define in4(a,b,c,d) int a,b,c,d; cin>>a>>b>>c>>d
#define vin(v,n); vi v(n); f0r(i,n){cin>>v[i];}
#define out(a) cout<<a<<'\n'
#define out2(a,b) cout<<a<<' '<<b<<'\n'
#define out3(a,b,c) cout<<a<<' '<<b<<' '<<c<<'\n'
#define out4(a,b,c,d) cout<<a<<' '<<b<<' '<<c<<' '<<d<<'\n'
#define vout(v) for(auto u : v){cout<<u<<' ';} cout<<'\n'
#define dout(a) cout<<a<<' '<<#a<<'\n'
#define dout2(a,b) cout<<a<<' '<<#a<<' '<<b<<' '<<#b<<'\n'
#define yn(x); if(x){cout<<"YES"<<'\n';}else{cout<<"NO"<<'\n';}
const int leg = 1e9 + 7;
const int mod = 998244353;
using namespace std;
const int mxn = 1005;
const int mxm = 11;
char grid[mxn][mxm];
bool vis[mxn][mxm];
int n,m;
int turns = 0;
vi w;
void dfs(int x, int y, int d, int l, int must){
//cout<<x<<' '<<y<<' '<<d<<' '<<l<<' '<<must<<'\n';
vis[x][y] = 1;
bool done = 0;
if(x + 1 < n && grid[x+1][y] == '#' && !vis[x+1][y]){
done = 1;
//if((d != 1 && l != 1) || must)turns++;
if(d == 1){
dfs(x+1, y, 1, l+1, must);
}
else{
w.pb(l);
dfs(x+1, y, 1, 1, (l == 1));
}
}
if(x - 1 >= 0 && grid[x-1][y] == '#' && !vis[x-1][y]){
done = 1;
// if((d != 2 && l != 1) || must)turns++;
if(d == 2){
dfs(x-1, y, 2, l+1, must);
}
else{
w.pb(l);
dfs(x-1, y, 2, 1, (l == 1));
}
}
if(y + 1 < m && grid[x][y+1] == '#' && !vis[x][y+1]){
done = 1;
// if((d != 3 && l != 1) || must)turns++;
if(d == 3){
dfs(x, y+1, 3, l+1, must);
}
else{
w.pb(l);
dfs(x, y+1, 3, 1, !must);
}
}
if(y - 1 >= 0 && grid[x][y-1] == '#' && !vis[x][y-1]){
done = 1;
// if((d != 4 && l != 1) || must)turns++;
if(d == 4){
dfs(x, y-1, 4, l+1, must);
}
else{
w.pb(l);
dfs(x, y-1, 4, 1, (l == 1));
}
}
if(!done)w.pb(l+1);
}
signed main(){
ios::sync_with_stdio(false);
cin.tie(NULL);
//ifstream cin(".in");
//ofstream cout(".out");
cin>>n>>m;
f0r(i,n)f0r(j,m)cin>>grid[i][j];
f0r(i,n)f0r(j,m)vis[i][j] = 0;
f0r(i,n){
f0r(j,m){
if(grid[i][j] == '#' && !vis[i][j]){
w.clear();
dfs(i, j, -1, 0, 1);
// vout(w);
if(w[0] != 0){
turns++;
}
else{
vi x;
if(w[1] == 1)x.pb(1);
FOR(i, 1, w.size())x.pb(w[i]);
int st = 0;
int ans = 0;
f0r(i, x.size()){
if(x[i] != 0)ans++;
if(x[i] == 1){
st++;
}
else{
ans -= (st + 1) / 2;
st = 0;
}
}
ans -= (st + 1) / 2;
turns += ans;
}
}
}
}
out(turns);
}
