java.lang.Object
g2301_2400.s2327_number_of_people_aware_of_a_secret.Solution

public class Solution extends java.lang.Object
2327 - Number of People Aware of a Secret.

Medium

On day 1, one person discovers a secret.

You are given an integer delay, which means that each person will share the secret with a new person every day , starting from delay days after discovering the secret. You are also given an integer forget, which means that each person will forget the secret forget days after discovering it. A person cannot share the secret on the same day they forgot it, or on any day afterwards.

Given an integer n, return the number of people who know the secret at the end of day n. Since the answer may be very large, return it modulo 109 + 7.

Example 1:

Input: n = 6, delay = 2, forget = 4

Output: 5

Explanation:

Day 1: Suppose the first person is named A. (1 person)

Day 2: A is the only person who knows the secret. (1 person)

Day 3: A shares the secret with a new person, B. (2 people)

Day 4: A shares the secret with a new person, C. (3 people)

Day 5: A forgets the secret, and B shares the secret with a new person, D. (3 people)

Day 6: B shares the secret with E, and C shares the secret with F. (5 people)

Example 2:

Input: n = 4, delay = 1, forget = 3

Output: 6

Explanation:

Day 1: The first person is named A. (1 person)

Day 2: A shares the secret with B. (2 people)

Day 3: A and B share the secret with 2 new people, C and D. (4 people)

Day 4: A forgets the secret. B, C, and D share the secret with 3 new people. (6 people)

Constraints:

  • 2 <= n <= 1000
  • 1 <= delay < forget <= n
  • Constructor Summary

    Constructors
    Constructor
    Description
     
  • Method Summary

    Modifier and Type
    Method
    Description
    int
    peopleAwareOfSecret(int n, int delay, int forget)
     

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
  • Constructor Details

    • Solution

      public Solution()
  • Method Details

    • peopleAwareOfSecret

      public int peopleAwareOfSecret(int n, int delay, int forget)