Solution:

def replace(r,c,n,R,C):
    count=0
    for i in range(r-n,r+n+1):
        for j in range(c-n,c+n+1):
            if(i>=0 and i<R and j>=0 and j<C and a[i][j]!="#"):
                a[i][j]="#"
                count+=1
    return count
r,c=map(int,input().split())
l=[]
a=[]
count=0
for i in range(r):
    l.append(input().split())
    a.append(["0" for i in range(c)])
for i in range(r):
    for j in range(c):
        if(l[i][j]=="S"):
            count+=replace(i,j,1,r,c) 
        elif(l[i][j]=="L"):
            count+=replace(i,j,2,r,c) 
print(count)


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