add JS solution for 0141 0160

Author: limbowandering

solution/0141.Linked List Cycle/Solution2.js

@@ -0,0 +1,24 @@
+var hasCycle2 = function(head) {
+  let slow = head
+  let fast = head
+  while (fast !== null && fast.next !== null) {
+    slow = slow.next
+    fast = fast.next.next
+    if (slow === fast) {
+      return true
+    }
+  }
+  return false
+}
+
+var hasCycle3 = function(head) {
+  let arr = []
+  while (head !== null) {
+    if (arr.includes(head)) {
+      return true
+    }
+    arr.push(head)
+    head = head.next
+  }
+  return false
+}

solution/0160.Intersection of Two Linked Lists/Solution.js

@@ -0,0 +1,45 @@
+var getIntersectionNode2 = function(headA, headB) {
+  if (!headA || !headB) {
+    return null
+  }
+  let q = headA, p = headB
+  let lengthA = 1
+  let lengthB = 1
+  while(q.next) {
+    q = q.next
+    lengthA++
+  }
+  while (p.next) {
+    p = p.next
+    lengthB++
+  }
+  if (q !== p) {
+    return null 
+  }
+
+  q = headA, p = headB
+  if (lengthA > lengthB) {
+    for (let i = 0; i < lengthA - lengthB; i++) {
+      q = q.next
+    }
+  } else {
+    for (let i = 0; i < lengthB - lengthA; i++) {
+      p = p.next
+    }
+  }
+  while (q !== p && q !== null) {
+    q = q.next
+    p = p.next
+  }
+  return q
+};
+
+var getIntersectionNode = function(headA, headB) {
+  let p1 = headA;
+	let p2 = headB;
+	while (p1 != p2) {
+		p1 = p1 ? p1.next : headB;
+		p2 = p2 ? p2.next : headA;
+	}
+	return p1;
+}