Iahub likes chess very much. He even invented a new chess piece named Coder. A Coder can move (and attack) one square horizontally or vertically. More precisely, if the Coder is located at position (*x*, *y*), he can move to (or attack) positions (*x* + 1, *y*), (*x*–1, *y*), (*x*, *y* + 1) and (*x*, *y*–1).

Iahub wants to know how many Coders can be placed on an *n* × *n* chessboard, so that no Coder attacks any other Coder.
The first line contains an integer *n* (1 ≤ *n* ≤ 1000).
# import sys
# sys.stdin=open("input.in","r")
# sys.stdout=open("output.out","w")
N=int(input())
L=[['.' for i in range(N)]for j in range(N)]
count=0
for i in range(N):
	for j in range(N):
		if i%2==0:
			if j%2==0:
				L[i][j]='C'
				count+=1
		else:
			if j%2!=0:
				L[i][j]='C'
				count+=1
print(count)
print(L)