# 1101. The Earliest Moment When Everyone Become Friends ## Description There are n people in a social group labeled from `0` to `n - 1`. You are given an array `logs` where `logs[i] = [timestampi, xi, yi]` indicates that `xi` and `yi` will be friends at the time `timestampi`. Friendship is **symmetric**. That means if `a` is friends with `b`, then `b` is friends with `a`. Also, person `a` is acquainted with a person `b` if `a` is friends with `b`, or `a` is a friend of someone acquainted with `b`. Return *the earliest time for which every person became acquainted with every other person*. If there is no such earliest time, return `-1`. **Example 1:** ``` **Input:** logs = [[20190101,0,1],[20190104,3,4],[20190107,2,3],[20190211,1,5],[20190224,2,4],[20190301,0,3],[20190312,1,2],[20190322,4,5]], n = 6 **Output:** 20190301 **Explanation:** The first event occurs at timestamp = 20190101 and after 0 and 1 become friends we have the following friendship groups [0,1], [2], [3], [4], [5]. The second event occurs at timestamp = 20190104 and after 3 and 4 become friends we have the following friendship groups [0,1], [2], [3,4], [5]. The third event occurs at timestamp = 20190107 and after 2 and 3 become friends we have the following friendship groups [0,1], [2,3,4], [5]. The fourth event occurs at timestamp = 20190211 and after 1 and 5 become friends we have the following friendship groups [0,1,5], [2,3,4]. The fifth event occurs at timestamp = 20190224 and as 2 and 4 are already friends anything happens. The sixth event occurs at timestamp = 20190301 and after 0 and 3 become friends we have that all become friends. ``` **Example 2:** ``` **Input:** logs = [[0,2,0],[1,0,1],[3,0,3],[4,1,2],[7,3,1]], n = 4 **Output:** 3 ``` **Constraints:** * `2 <= n <= 100` * `1 <= logs.length <= 104` * `logs[i].length == 3` * `0 <= timestampi <= 109` * `0 <= xi, yi <= n - 1` * `xi != yi` * All the values `timestampi` are **unique**. * All the pairs `(xi, yi)` occur at most one time in the input. ## ac ```java ```