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).
n = int(input())
x = 0
l = [['.' for _ in range(n+2)] for _ in range(n+2)]
for i in range(1,len(l)-1):
    for j in range(1,len(l)-1):
        if l[i][j+1] != 'C' and l[i][j-1] != 'C' and l[i+1][j] != 'C' and l[i-1][j] != 'C':
            l[i][j] = 'C'
            x+=1
print(x)
for i in range(1,len(l)-1):
    for j in range(1,len(l)-1):
        print(l[i][j],end="")
    print()