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())
foo = temp = 0
arr = [[foo for i in range(n)] for j in range(n)]
for i in range(n):
    for j in range(n):
        if(i%2==0 and j%2==1):
            arr[i][j]='C'
            temp+=1
            continue
        if(i%2==1 and j%2==0):
            arr[i][j]='C'
            temp+=1
            continue
        else:
            arr[i][j]='.'
print(temp)
for i in range(n):
    for j in range(n):
        print(arr[i][j],end='')
    print("")
        


