#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
#ifdef APURBA
#include "DEBUG_TEMPLATE.h"
#else
#define HERE
#define debug(args...)
#endif
#define ALL(x) x.begin(),x.end()


vector<string> getString(vector<string>s , int i1, int j1, int i2, int j2)
{
    vector<string>ret;
    for(int i=i1;i<=i2;i++)
    {
        string now = "";
        for(int j=j1;j<=j2;j++)
        {
            now += s[i][j];
        }
        ret.push_back(now);
    }
    return ret;
}
ll solve(vector<string>s)
{
    int pos = -1;
    int n = s.size();
    int m = s[0].size();
    for(int i=0;i<m;i++)
    {
        if(s[0][i]!='.'){
            assert(pos==-1);
            pos = i;
        }
    }
    assert(pos != -1);
    if(s[0][pos]>='0' && s[0][pos]<='9')
    {
        return s[0][pos] - '0';
    }
    vector<string>a = getString(s, 1, 0, n-1, pos-1);
    vector<string>b = getString(s, 1, pos+1, n-1, m-1);
    ll x1 = solve(a);
    ll x2 = solve(b);
    if(s[0][pos]=='+')
    {
        return x1+x2;
    }
    else if(s[0][pos]=='-')
    {
        return x1-x2;
    }
    else{
        assert(s[0][pos]=='*');
        return x1*x2;
    }


}

void TEST_CASES()
{
    int n,m;
    cin>>n>>m;
    vector<string>s(n);
    for(int i=0; i<n; i++)
    {
        cin>>s[i];
    }
    ll ans = solve(s);
    cout<<ans<<"\n";
}


/*
*/

int32_t main()
{
#ifndef APURBA
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
#endif
    //freopen("input.txt","r",stdin);
    //freopen("out1.txt","w",stdout);
    int t=1;
    //cin>>t;
    while(t--)
    {
        TEST_CASES();
    }
    return 0;
}