#include<bits/stdc++.h>
using namespace std;
#define re register
const int N=55,M=3005;
int n,m;
char s[N][N];
int cnt_x=0,cnt_y=0;
int be_x[N][N],be_y[N][N];
int c[M][M]={0};
int sx[M],sy[M],us[M];
int ans=0;
inline bool work(int u){
    for(re int v=1;v<=cnt_y;v++){
        if(c[u][v]&&!us[v]){
            us[v]=1;
            if(sy[v]==-1||work(sy[v])){
                sx[u]=v;
                sy[v]=u;
                return 1;
            }
        }
    }
    return 0;
}
int main(){
    memset(sx,-1,sizeof(sx));
    memset(sy,-1,sizeof(sy));
    scanf("%d%d",&n,&m);
    for(re int i=1;i<=n;i++){
        for(re int j=1;j<=m;j++){
            char c;
            cin>>c;
            s[i][j]=c;
        }
    }
    for(re int i=1;i<=n;i++){
        for(re int j=1;j<=m;j++){
            if(s[i][j]==‘#‘) continue;
            if(j==1||s[i][j-1]==‘#‘){
                cnt_x++;
                be_x[i][j]=cnt_x;
            }
            else be_x[i][j]=be_x[i][j-1];
        }
    }
    /*
    for(re int i=1;i<=n;i++){
        for(re int j=1;j<=m;j++){
            cout<<be_x[i][j]<<" ";
        }
        cout<<endl;
    }
    */
    for(re int j=1;j<=m;j++){
        for(re int i=1;i<=n;i++){
            if(s[i][j]==‘#‘) continue;
            if(i==1||s[i-1][j]==‘#‘){
                cnt_y++;
                be_y[i][j]=cnt_y;
            }
            else be_y[i][j]=be_y[i-1][j];
        }
    }
    /*
    for(re int i=1;i<=n;i++){
        for(re int j=1;j<=m;j++){
            cout<<be_y[i][j]<<" ";
        }
        cout<<endl;
    }
    */
    for(re int i=1;i<=n;i++){
        for(re int j=1;j<=m;j++){
            if(s[i][j]!=‘*‘) continue;
            c[be_x[i][j]][be_y[i][j]]=1;
        }
    }
    for(int i=1;i<=cnt_x;i++){
        memset(us,0,sizeof(us));
        ans+=work(i);
    }
    printf("%d\n",ans);
    return 0;
}