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())
count=0
a=[[0 for _ in range(n)]for _ in range (n)]
for i in range(n):
    for j in range(n):
        check=[]
        if i-1>=0:
            check.append(a[i-1][j])
        if i+1<n:
            check.append(a[i+1][j])
        if j-1>=0:
            check.append(a[i][j-1])
        if j+1<n:
            check.append(a[i][j+1])
        if 'C' not in check:
            a[i][j]='C'
            count+=1 
        else:
            a[i][j]='.'
        
        
print(count)
for i in range(n):
    for j in range(n):
        print(a[i][j],end="")
    print()