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())
l=[]
cnt=0
for z in range(n):
    s=""
    if z%2==0:
        for y in range(n):
            if y%2==0:
                s+="C"
                cnt+=1
            else :
                s+="."
    else :
        for y in range(n):
            if y%2==0:
                s+="."
            else :
                s+="C"
                cnt+=1
    l.append(s)
print(cnt)
print(*l,sep="\n")