Codeforces Round 484 (Div. 2)
A
Row
Codeforces
1200
原题
←B →
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You're given a row with $n$ chairs. We call a seating of people "maximal" if the two following conditions hold:

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  1. There are no neighbors adjacent to anyone seated.
  2. It's impossible to seat one more person without violating the first rule.
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The seating is given as a string consisting of zeros and ones ($0$ means that the corresponding seat is empty, $1$ — occupied). The goal is to determine whether this seating is "maximal".

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Note that the first and last seats are not adjacent (if $n \ne 2$).

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Input

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The first line contains a single integer $n$ ($1 \leq n \leq 1000$) — the number of chairs.

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The next line contains a string of $n$ characters, each of them is either zero or one, describing the seating.

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Output

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Output "Yes" (without quotation marks) if the seating is "maximal". Otherwise print "No".

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You are allowed to print letters in whatever case you'd like (uppercase or lowercase).

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Note

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In sample case one the given seating is maximal.

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In sample case two the person at chair three has a neighbour to the right.

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In sample case three it is possible to seat yet another person into chair three.

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样例

Input #1
3
101
Output #1
Yes
InputCopy OutputCopy
Input #2
4
1011
Output #2
No
InputCopy OutputCopy
Input #3
5
10001
Output #3
No
InputCopy OutputCopy
题目信息
题号
982A
时间限制
1 s
内存限制
256 MB
标签
暴力
构造

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