m,n=input().split() m,n=int(m),int(n) a=[] for x in range(m): tmp=list(map(int,input().split())) a.append(tmp) b=[] for x in range(m): tmp=list(map(int,input().split())) b.append(tmp) count=0; for i in range(m): for j in range(n): if a[i][j]==b[i][j]: count+=1 print("{:.2f}".format(count/(m*n)*100))