Update index.ts

Author: masx200

tree-of-coprimes/index.ts

@@ -1,51 +1,58 @@
-export default getCoprimes;
-function getCoprimes(nums: number[], edges: number[][]): number[] {
-    const edge = Array(nums.length)
-        .fill(0)
-        .map(() => Array<number>());
-    for (const [a, b] of edges) {
-        edge[a].push(b);
-        edge[b].push(a);
-    }
-
-    if (prime.length === 0) {
-        for (const i of Array(51).keys()) {
-            prime[i] = Array(51).fill(false);
-        }
-
-        for (const i of Array(51).keys())
-            for (let j = i; j < 51; j++) {
-                prime[i][j] = prime[j][i] = greatestCommonDivisor(i, j) === 1;
-            }
-    }
-
-    const visited = new Set<number>();
-    function dfs(node: number, ancestors: number[]) {
-        if (!visited.has(node)) {
-            visited.add(node);
-
-            if (ancestors.length) {
-                for (let i = ancestors.length - 1; i >= 0; i--) {
-                    if (prime[nums[node]][nums[ancestors[i]]]) {
-                        results[node] = ancestors[i];
-                        break;
-                    }
-                }
-            }
-            for (const child of edge[node]) {
-                ancestors.push(node);
-                dfs(child, ancestors);
-                ancestors.pop();
-            }
-        }
-    }
-    const results: number[] = Array(nums.length).fill(-1);
-    dfs(0, []);
-    return results;
-}
-
-const prime: boolean[][] = [];
-
-function greatestCommonDivisor(a: number, b: number): number {
-    return b != 0 ? greatestCommonDivisor(b, a % b) : a;
-}
+import { greatestCommonDivisor } from "../max-points-on-a-line/greatest_common_divisor.ts";
+
+export default getCoprimes;
+function getCoprimes(nums: number[], edges: number[][]): number[] {
+    const edge = Array(nums.length)
+        .fill(0)
+        .map(() => Array<number>());
+    for (const [a, b] of edges) {
+        edge[a].push(b);
+        edge[b].push(a);
+    }
+
+    if (prime.length === 0) {
+        for (const i of Array(51).keys()) {
+            prime[i] = Array(51).fill(false);
+        }
+
+        for (const i of Array(51).keys()) {
+            for (let j = i; j < 51; j++) {
+                prime[i][j] = prime[j][i] = greatestCommonDivisor(i, j) === 1;
+            }
+        }
+    }
+
+    const visited = new Set<number>();
+    const currents: [number, number][][] = Array(51)
+        .fill(0)
+        .map(() => []);
+    function dfs(node: number, depth: number) {
+        if (visited.has(node)) {
+            return;
+        }
+        visited.add(node);
+        const value = nums[node];
+
+        let ans = [-1, -1];
+        for (const i of Array(51).keys()) {
+            if (currents[i].length && prime[value][i]) {
+                const get = currents[i].at(-1) as [number, number];
+
+                if (get[1] > ans[1]) {
+                    ans = get;
+                }
+            }
+        }
+        results[node] = ans[0];
+        for (const child of edge[node]) {
+            currents[value].push([node, depth]);
+            dfs(child, depth + 1);
+            currents[value].pop();
+        }
+    }
+    const results: number[] = Array(nums.length).fill(-1);
+    dfs(0, 0);
+    return results;
+}
+
+const prime: boolean[][] = [];