m,n=list(map(int,input().split())) a=[] for i in range(m): tmp=list(map(int,input().split())) a.append(tmp) b=[] for i 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))