package possible_bipartition

Author: masx200

possible-bipartition/UnionFind.go

@@ -0,0 +1,53 @@
+package possible_bipartition
+
+type UnionFind struct {
+	parents, sizes map[int]int
+}
+
+func (u UnionFind) Size(x int) int {
+
+	v, o := u.sizes[x]
+	if o {
+		return v
+	} else {
+		return 1
+	}
+}
+func NewUnionFind() UnionFind {
+	parent := map[int]int{}
+
+	return UnionFind{parents: parent, sizes: map[int]int{}}
+}
+
+func (u UnionFind) Find(x int) int {
+	_, o := u.parents[x]
+	if !o {
+		u.parents[x] = x
+	}
+	if u.parents[x] != x {
+		u.parents[x] = u.Find(u.parents[x])
+	}
+	return u.parents[x]
+}
+
+func (u UnionFind) Union(x, y int) {
+	x, y = u.Find(x), u.Find(y)
+	if x == y {
+		return
+	}
+
+	u.sizes[x] = u.Size(x)
+	u.sizes[y] = u.Size(y)
+
+	if u.sizes[x] > u.sizes[y] {
+		u.parents[y] = x
+		u.sizes[x] = u.sizes[x] + u.sizes[y]
+	} else {
+		u.parents[x] = y
+		u.sizes[y] = u.sizes[x] + u.sizes[y]
+	}
+}
+
+func (u UnionFind) Connected(x, y int) bool {
+	return u.Find(x) == u.Find(y)
+}

possible-bipartition/export.go

@@ -0,0 +1,5 @@
+package possible_bipartition
+
+func PossibleBipartition(n int, dislikes [][]int) bool {
+	return possibleBipartition(n, dislikes)
+}

possible-bipartition/index.go

@@ -0,0 +1,20 @@
+package possible_bipartition
+
+func possibleBipartition(n int, dislikes [][]int) bool {
+	g := make([][]int, n)
+	for _, d := range dislikes {
+		x, y := d[0]-1, d[1]-1
+		g[x] = append(g[x], y)
+		g[y] = append(g[y], x)
+	}
+	uf := NewUnionFind()
+	for x, nodes := range g {
+		for _, y := range nodes {
+			uf.Union(nodes[0], y)
+			if uf.Connected(x, y) {
+				return false
+			}
+		}
+	}
+	return true
+}

possible-bipartition/index.kt

@@ -0,0 +1 @@
+package masx200.leetcode_test.possible_bipartition

possible-bipartition/index.ts

@@ -1,25 +1,25 @@
-import { UnionFind } from "../largest-component-size-by-common-factor/UnionFind.ts";
-export default function possibleBipartition(
-    n: number,
-    dislikes: number[][]
-): boolean {
-    const uf = new UnionFind();
-
-    const e = Array<Array<number>>(n + 1);
-
-    for (const [a, b] of dislikes) {
-        e[a] ??= [];
-        e[b] ??= [];
-        e[a].push(b);
-        e[b].push(a);
-    }
-
-    for (const i of Object.keys(e)) {
-        for (const d of e[Number(i)]) {
-            uf.union(d, e[Number(i)][0]);
-            if (uf.connected(d, Number(i))) return false;
-        }
-    }
-
-    return true;
-}
+import { UnionFind } from "../largest-component-size-by-common-factor/UnionFind.ts";
+export default function possibleBipartition(
+    n: number,
+    dislikes: number[][],
+): boolean {
+    const uf = new UnionFind();
+
+    const e = Array<Array<number>>(n + 1);
+
+    for (const [a, b] of dislikes) {
+        e[a] ??= [];
+        e[b] ??= [];
+        e[a].push(b);
+        e[b].push(a);
+    }
+
+    for (const i of Object.keys(e)) {
+        for (const d of e[Number(i)]) {
+            uf.union(d, e[Number(i)][0]);
+            if (uf.connected(d, Number(i))) return false;
+        }
+    }
+
+    return true;
+}