LCS

题号：NC224146
时间限制：C/C++/Rust/Pascal 1秒，其他语言2秒
空间限制：C/C++/Rust/Pascal 256 M，其他语言512 M
Special Judge, 64bit IO Format: %lld

题目描述

Let $LCS(s_1,s_2)$ denote the length of the longest common subsequence (not necessary continuity) of string $s_1$ and string $s_2$ .

Now give you four integers $a,b,c,n$ , you need to find three lowercase character strings $s_1,s_2,s_3$ satisfy that $|s_1|=|s_2|=|s_3|=n$

and $LCS(s_1,s_2)=a, LCS(s_2,s_3)=b, LCS(s_1,s_3)=c$ .

输入描述:

The first line has four integers .

.

.

输出描述:

If there is no solution, output "NO" (without double quotation marks).

If there exists solutions, you only need to output any one: output three lines, the i-th line has one strings .

示例1

输入

复制

1 2 3 4

输出

复制

aqcc
abpp
abcc

示例2

输入

复制

1 2 3 3

输出

复制

NO