200672: [AtCoder]ARC067 E - Grouping

Memory Limit:256 MB Time Limit:2 S
Judge Style:Text Compare Creator:
Submit:0 Solved:0

Description

Score : $600$ points

Problem Statement

There are $N$ people, conveniently numbered $1$ through $N$. We want to divide them into some number of groups, under the following two conditions:

  • Every group contains between $A$ and $B$ people, inclusive.

  • Let $F_i$ be the number of the groups containing exactly $i$ people. Then, for all $i$, either $F_i=0$ or $C≤F_i≤D$ holds.

Find the number of these ways to divide the people into groups. Here, two ways to divide them into groups is considered different if and only if there exists two people such that they belong to the same group in exactly one of the two ways. Since the number of these ways can be extremely large, print the count modulo $10^9+7$.

Constraints

  • $1≤N≤10^3$
  • $1≤A≤B≤N$
  • $1≤C≤D≤N$

Input

The input is given from Standard Input in the following format:

$N$ $A$ $B$ $C$ $D$

Output

Print the number of ways to divide the people into groups under the conditions, modulo $10^9+7$.


Sample Input 1

3 1 3 1 2

Sample Output 1

4

There are four ways to divide the people:

  • $(1,2),(3)$
  • $(1,3),(2)$
  • $(2,3),(1)$
  • $(1,2,3)$

The following way to divide the people does not count: $(1),(2),(3)$. This is because it only satisfies the first condition and not the second.


Sample Input 2

7 2 3 1 3

Sample Output 2

105

The only ways to divide the people under the conditions are the ones where there are two groups of two people, and one group of three people. There are $105$ such ways.


Sample Input 3

1000 1 1000 1 1000

Sample Output 3

465231251

Sample Input 4

10 3 4 2 5

Sample Output 4

0

The answer can be $0$.

Input

题意翻译

有$N$个人,编号依次是$1,2,\cdots ,N$, 现在要将他们分成若干组,满足: - 每一组的人数均在$[A,B]$之间。 - 记$F_i$为当前分组方案中人数为$i$的组的数量,则$F_i$应满足$F_i=0$或$C\leq F_i\leq D$. 其中$A,B,C,D$均为给定值。 求本质不同的分组方案数对$10^9+7$取模后的结果。两种方案是本质不同的当且仅当存在两个人使得在第一种方案中他们在同一组,而在第二种方案中不是。 数据范围:$1\leq N\leq 10^3,1\leq A\leq B\leq N,1\leq C\leq D\leq N$

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