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).
#!/usr/bin/python
val = int(input())
f1 = 1
f2 = 1
ans_count = 0
Matrix = [[ '.' for x in range (val)] for x in range (val) ]
for i in range(val):
    if(i != 0):
        if(Matrix[i-1][0] == 'C'):f2 = 0
    for j in range(val):
        if(f1 == f2):
            ans_count += 1
            Matrix[i][j] = 'C'
        else:
            Matrix[i][j] = '.'
        if(f2 == 0): f2 = 1
        else : f2 = 0
print(ans_count)
for i in range(val):
    for j in range(val):
        print(Matrix[i][j], end = "")
    print()

