Codeforces Round 233 (Div. 2)
C
Cards
Codeforces
未评级
原题
← BD →
翻译中…

User ainta loves to play with cards. He has $*a*$ cards containing letter "o" and $*b*$ cards containing letter "x". He arranges the cards in a row, and calculates the score of the deck by the formula below.

翻译中…
  1. At first, the score is $0$.
  2. For each block of contiguous "o"s with length $*x*$ the score increases by $*x*^{2}$.
  3. For each block of contiguous "x"s with length $*y*$ the score decreases by $*y*^{2}$.
翻译中…

For example, if $*a* = 6, *b* = 3$ and ainta have arranged the cards in the order, that is described by string "ooxoooxxo", the score of the deck equals $2^{2} - 1^{2} + 3^{2} - 2^{2} + 1^{2} = 9$. That is because the deck has 5 blocks in total: "oo", "x", "ooo", "xx", "o".

翻译中…

User ainta likes big numbers, so he wants to maximize the score with the given cards. Help ainta make the score as big as possible. Note, that he has to arrange all his cards.

翻译中…

Input

翻译中…

The first line contains two space-separated integers $*a*$ and $*b*$ ($0 ≤ *a*, *b* ≤ 10^{5}; *a* + *b* ≥ 1$) — the number of "o" cards and the number of "x" cards.

翻译中…

Output

翻译中…

In the first line print a single integer $*v*$ — the maximum score that ainta can obtain.

翻译中…

In the second line print $*a* + *b*$ characters describing the deck. If the $*k*$-th card of the deck contains "o", the $*k*$-th character must be "o". If the $*k*$-th card of the deck contains "x", the $*k*$-th character must be "x". The number of "o" characters must be equal to $*a*$, and the number of "x " characters must be equal to $*b*$. If there are many ways to maximize $*v*$, print any.

翻译中…

Please, do not write the %lld specifier to read or write 64-bit integers in С++. It is preferred to use the cin, cout streams or the %I64d specifier.

翻译中…

样例

Input #1
2 3
Output #1
-1
xoxox
InputCopy OutputCopy
Input #2
4 0
Output #2
16
oooo
InputCopy OutputCopy
Input #3
0 4
Output #3
-16
xxxx
InputCopy OutputCopy
题目信息
题号
399C
时间限制
1 s
内存限制
256 MB

题面与样例版权归 Codeforces 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。