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).
players = int(input().lstrip().rstrip())

numOfCoders = 0
skipOrNoSkip = False
result = []
for i in range(0, players):
    row = ["."]*players
    for idx, letter in enumerate(row):
        if not skipOrNoSkip:
            letter = "C"
            numOfCoders += 1
        skipOrNoSkip = not skipOrNoSkip
        result.append(letter)
    result.append("\n")

print(numOfCoders)
print("".join(result))
