def fun1(x,y) :
        global obp
        obr=obp
        for i in range(nd):
                for j in range(msd)
n=int(input())
m=int(input())
pd=[]
po=[]
obp=[]
d=[]
o=[]
pw=0
for i in range(60):
        obp.append([0]*60)
for i in range(n):
        spd=[]
        spd1=input()
        for c in spd1:
                spd.append(c)
        pd.append(spd)
for i in range(n):
        spo=[]
        spo1=input()
        for c in spo1:
                spo.append(c)
        po.append(spo)
for i in range(n):
        sd=[]
        for j in range(m):
                if pd[i][j]=='H':
                        sd.append('H')
                if po[i][j]=='W':
                        obp[i+20][j+20]='W'
        d.append(sd)
        if sd>msd:
                msd=sd
d=d
nd=len(d)
for i in range(60):
        for j in range(60):
                if obp[i][j]=='W' and (obp[i+1][j]!='W' or obp[i][j+1]!='W' or obp[i-1][j]!='W' or obp[i][j-1]!='W'):
                        pw=pw+1
while k<=pw:
        for i in range(60):
                for j in range(60):
                        if obp[i][j]=='W' and  obp[i-1][j]!='W':
                                fun1(i-1,j)