#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <list>
#include <utility>
#include <cstring>
#include <set>

using namespace std;

int w, h;
int sx, sy;
int table[20][20];
int reach[20][20];
set<pair<int, int> > up;

void Run(int x, int y)
{
  if(x < 0 || y < 0 || x >= w || y >= h)
    return;
  if(!table[x][y] || reach[x][y])
    return;
  reach[x][y] = 1;
  up.insert(make_pair(x,y));
}

int main()
{
  while(cin >> w >> h) {
    if(w == 0)
      break;
    for(int i = 0; i < h; ++i) {
      string line;
      cin >> line;
      for(int j = 0; j < w; ++j) {
        if(line[j] == '#') {
          table[j][i] = 0;
        } else {
          table[j][i] = 1;
          if(line[j] == '@') {
            sx = j; sy = i;
          }
        }
      }
    }
    memset(reach, 0, sizeof(reach));
    reach[sx][sy] = 1;
    up.clear();
    up.insert(make_pair(sx, sy));
    while(!up.empty()) {
      int x = up.begin()->first;
      int y = up.begin()->second;
      up.erase(up.begin());
      Run(x+1,y);
      Run(x-1,y);
      Run(x,y+1);
      Run(x,y-1);
    }
    int r = 0;
    for(int i = 0; i < w; ++i)
      for(int j = 0; j < h; ++j)
        if(reach[i][j])
          ++r;
    cout << r << endl;
  }
}