a,b = map(int,input().split())
okrug = (a+b-1)//b
if okrug % 2 != 0:
    x = max(0,okrug // 2)
else:
    x = okrug // 2 -1
y = 0
nm = 0
z = []
if a == 1 and b == 1:
    cc = 0.0
    z = [[0]]
else:

    for i in range(okrug):
        z.append([])
        if i != okrug - 1:
            for j in range(b):
                xy = min(abs(i-x)+ abs(j-y),x+1+abs(i-okrug+1)+ abs(j-max(a % b -1 ,1)),1 + abs(x-1-i) + abs(b-1-j))

                z[i].append(xy)
                nm += xy

        else:
            if a % b == 0:
                uyu = b
            else:
                uyu = a % b
            for j in range(uyu):

                xy = min(abs(i-x)+ abs(j-y),x+1+abs(i-okrug+1)+ abs(j-max(uyu - 1,1)),1 + abs(x-1-i) + abs(b-1-j))
                z[i].append(xy)

                nm += xy
    cc = round(nm / a,2)
if len(str(cc)[str(cc).index('.')+1::]) == 2:
    print('Mean'+ ' = ' + str(cc))
else:
    print('Mean'+ ' = ' + str(cc)+'0')
for i in z:
    print(*i)