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).
def coders(n):
    
    solution = []
    for i in range(n):
        inner = []
        f = (i % 2 == 0)
        for j in range(n):
            f1 = (j % 2 == 0)
            if f:
                if f1:
                    inner.append("C")
                else:
                    inner.append(".")
            else:
                if f1:
                    inner.append(".")
                else:
                    inner.append("C")
        solution.append(inner)

    print(n)
    for i in range(n):
        print("".join(solution[i]))

if __name__ == '__main__':
	n = int(input().strip())
	coders(n)