32-SeongHoonC

SeongHoonC/유니온파인드/집합의표현.kt

@@ -0,0 +1,43 @@
+import java.io.BufferedReader
+import java.io.InputStreamReader
+
+private lateinit var br: BufferedReader
+private lateinit var parents: Array<Int>
+
+fun main() {
+    br = BufferedReader(InputStreamReader(System.`in`))
+    val (n, m) = br.readLine().split(" ").map { it.toInt() }
+    parents = Array(n + 1) { it }
+
+    repeat(m) {
+        val (command, a, b) = br.readLine().split(" ").map { it.toInt() }
+        if (command == 0) {
+            union(a, b)
+        } else {
+            println(if (findParents(a) == findParents(b)) "YES" else "NO")
+        }
+    }
+}
+
+private fun findParents(a: Int): Int {
+    var parent = parents[a]
+    while (parents[parent] != parent) {
+        parent = parents[parent]
+    }
+    parents[a] = parent
+    return parent
+}
+
+private fun union(a: Int, b: Int) {
+    val parentA = findParents(a)
+    val parentB = findParents(b)
+
+    if (parentA == parentB) {
+        return
+    }
+    if (parentA > parentB) {
+        parents[parentA] = parentB
+        return
+    }
+    parents[parentB] = parentA
+}