def dfs(x,y):
    b[x][y]=1
    a[x][y]="#"
    for i in range(4):
        tx=x+tr[i][0]
        ty=y+tr[i][1]
        if(tx>=0 and tx<h and ty>=0 and ty<w):
            if(b[tx][ty]==0 and a[tx][ty]=="."):
                dfs(tx,ty)
    return
sr=input().split()
w=int(sr[0])
h=int(sr[1])
a=[[0 for i in range(w)] for j in range(h)]
b=[[0 for i in range(w)] for j in range(h)]
tr=[[-1,0],[1,0],[0,-1],[0,1]]
x=0
y=0
for i in range(h):
    sr=input()
    for j in range(w):
        a[i][j]=sr[j:j+1]
        if(a[i][j]=="@"):
            x=i
            y=j
dfs(x,y)
k=0
for i in range(h):
    for j in range(w):
        if(b[i][j]==1):
            k=k+1
print(k)

/**************************************************************
	Problem: 1897
	User: admin
	Language: Python
	Result: Accepted
	Time:181 ms
	Memory:34488 kb
****************************************************************/