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codeforces 967 D Resource Distribution

題目

One department of some software company has n servers of different specifications. Servers are indexed with consecutive integers from 1 to n. Suppose that the specifications of the j-th server may be expressed with a single integer number cj of artificial resource units.

In order for production to work, it is needed to deploy two services S

1 and S2 to process incoming requests using the servers of the department. Processing of incoming requests of service Si takes xi resource units.

The described situation happens in an advanced company, that is why each service may be deployed using not only one server, but several servers simultaneously. If service S

i is deployed using ki servers, then the load is divided equally between these servers and each server requires only xi/ki (that may be a fractional number) resource units.

Each server may be left unused at all, or be used for deploying exactly one of the services (but not for two of them simultaneously). The service should not use more resources than the server provides.

Determine if it is possible to deploy both services using the given servers, and if yes, determine which servers should be used for deploying each of the services.

Input
The first line contains three integers n, x1, x2 (2n300000, 1x1,x2109) — the number of servers that the department may use, and resource units requirements for each of the services.

The second line contains n space-separated integers c1,c2,...,cn (1ci109) — the number of resource units provided by each of the servers.

Output
If it is impossible to deploy both services using the given servers, print the only word “No” (without the quotes).

Otherwise print the word “Yes” (without the quotes).

In the second line print two integers k1 and k2 (1k1,k2n) — the number of servers used for each of the services.

In the third line print k1 integers, the indices of the servers that will be used for the first service.

In the fourth line print k2 integers, the indices of the servers that will be used for the second service.

No index may appear twice among the indices you print in the last two lines. If there are several possible answers, it is allowed to print any of them.

Examples

Input
6 8 16
3 5 2 9 8 7
Output
Yes
3 2
1 2 6
5 4

Input
4 20 32
21 11 11 12
Output
Yes
1 3
1
2 3 4

Input
4 11 32
5 5 16 16
Output
No

Input
5 12 20
7 8 4 11 9
Output
No

Note
In the first sample test each of the servers 1, 2 and 6 will will provide 8/3=2.(6) resource units and each of the servers 5, 4 will provide 16/2=8 resource units.

In the second sample test the first server will provide 20 resource units and each of the remaining servers will provide 32/3=10.(6) resource units.

分析

【題意】
給出n個伺服器的資源數c1,c2,...,cn和執行2個程式需要的資源x1,x2,求一個解決方案

  • 選取k1個資源數不小於x1k1的伺服器使資源總和不小於x1
  • 選取k2個資源數不小於x2k2的伺服器使資源總和不小於x2
  • 兩次選取的伺服器不能有交叉

【分析】

  1. 伺服器貪心:連續選擇x1cmin個伺服器
    假設對於x1已經選擇了n個伺服器,要求每個伺服器的資源數都不小於x1n,只要最小的資源數不小於這個值就行了,也就是 cminx1ncminnx1。可以理解為,一個伺服器的集合實際上最多提供cminn個資源。那麼從貪心的角度