Package g1701_1800.s1733_minimum_number_of_people_to_teach

Class Solution

java.lang.Object

g1701_1800.s1733_minimum_number_of_people_to_teach.Solution

public class Solution
extends Object

1733 - Minimum Number of People to Teach.

Medium

On a social network consisting of m users and some friendships between users, two users can communicate with each other if they know a common language.

You are given an integer n, an array languages, and an array friendships where:

• There are n languages numbered 1 through n,
• languages[i] is the set of languages the ith user knows, and
• friendships[i] = [ui, vi] denotes a friendship between the users ui and vi.

You can choose one language and teach it to some users so that all friends can communicate with each other. Return the minimum number of users you need to teach.

Note that friendships are not transitive, meaning if x is a friend of y and y is a friend of z, this doesn’t guarantee that x is a friend of z.

Example 1:

Input: n = 2, languages = [[1],[2],[1,2]], friendships = [[1,2],[1,3],[2,3]]

Output: 1

Explanation: You can either teach user 1 the second language or user 2 the first language.

Example 2:

Input: n = 3, languages = [[2],[1,3],[1,2],[3]], friendships = [[1,4],[1,2],[3,4],[2,3]]

Output: 2

Explanation: Teach the third language to users 1 and 3, yielding two users to teach.

Constraints:

• 2 <= n <= 500
• languages.length == m
• 1 <= m <= 500
• 1 <= languages[i].length <= n
• 1 <= languages[i][j] <= n
• 1 <= ui < vi <= languages.length
• 1 <= friendships.length <= 500
• All tuples (ui, vi) are unique
• languages[i] contains only unique values

Constructor Summary

Constructors

Constructor	Description
Solution()

Method Summary

Modifier and Type	Method	Description
int	minimumTeachings(int n, int[][] languages, int[][] friendships)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Solution

public Solution()

Method Detail

minimumTeachings

public int minimumTeachings(int n,
                            int[][] languages,
                            int[][] friendships)