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).
grid = []
n = int(input())
cnt = 0
for i in range(n):
    grid.append([])
    for j in range(n):
        if ( i + j ) % 2 == 0:
            cnt += 1
            grid[i].append('C')
        else:
            grid[i].append('.')


print(cnt)

for i in range(n):
   print(grid[i])
        
    
