Codeforces Round 783 (Div. 2)
B
Social Distance
Codeforces
900
原题
← AC →
翻译中…

$m$ chairs are arranged in a circle sequentially. The chairs are numbered from $0$ to $m-1$. $n$ people want to sit in these chairs. The $i$-th of them wants at least $a[i]$ empty chairs both on his right and left side.

翻译中…

More formally, if the $i$-th person sits in the $j$-th chair, then no one else should sit in the following chairs: $(j-a[i]) \bmod m$, $(j-a[i]+1) \bmod m$, ... $(j+a[i]-1) \bmod m$, $(j+a[i]) \bmod m$.

翻译中…

Decide if it is possible to sit down for all of them, under the given limitations.

翻译中…

Input

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The input consists of multiple test cases. The first line contains a single integer $t$ ($1 \leq t \leq 5 \cdot 10^4$) — the number of test cases. The description of the test cases follows.

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The first line of each test case contains two integers $n$ and $m$ ($2 \leq n \leq 10^5$, $1 \leq m \leq 10^9$) — the number of people and the number of chairs.

翻译中…

The next line contains $n$ integers, $a_1$, $a_2$, ... $a_n$ ($1 \leq a_i \leq 10^9$) — the minimum number of empty chairs, on both sides of the $i$-th person.

翻译中…

It is guaranteed that the sum of $n$ over all test cases will not exceed $10^5$.

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Output

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For each test case print "YES" (without quotes) if it is possible for everyone to sit down and fulfil the restrictions, and "NO" (without quotes) otherwise.

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You may print every letter in any case you want (so, for example, the strings "yEs", "yes", "Yes" and "YES" will all be recognized as positive answers).

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Note

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Test case $1$: $n \gt m$, so they can not sit down.

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Test case $2$: the first person can sit $2$-nd and the second person can sit in the $0$-th chair. Both of them want at least $1$ empty chair on both sides, chairs $1$ and $3$ are free, so this is a good solution.

翻译中…

Test case $3$: if the second person sits down somewhere, he needs $2$ empty chairs, both on his right and on his left side, so it is impossible to find a place for the first person, because there are only $5$ chairs.

翻译中…

Test case $4$: they can sit in the $1$-st, $4$-th, $7$-th chairs respectively.

翻译中…

样例

Input #1
6
3 2
1 1 1
2 4
1 1
2 5
2 1
3 8
1 2 1
4 12
1 2 1 3
4 19
1 2 1 3
Output #1
NO
YES
NO
YES
NO
YES
InputCopy OutputCopy
题目信息
题号
1668B
时间限制
1.5 s
内存限制
256 MB
标签
贪心
数学
排序

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