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).
from sys import stdin; inp = stdin.readline
from math import dist, ceil, floor, sqrt, log
def IA(): return list(map(int, inp().split()))
def FA(): return list(map(float, inp().split()))
def SA(): return inp().split()
def I(): return int(inp())
def F(): return float(inp())
def S(): return inp()

def main():
    n = I()
    if n%2==0:
        res = n//2 * n 
    else:
        a = (n+1)//2
        b = n-a
        res = pow(a, 2) + pow(b, 2)
    print(res)
    
    for i in range(n):
        if i%2==0:
            for j in range(n):
                if j%2==0:
                    print('C', end='')
                else: 
                    print('.', end='')
            print()
        else:
            for j in range(n):
                if j%2==1:
                    print('C', end='')
                else:
                    print('.', end='')
            print()

if __name__ == '__main__':
    main()