diff --git a/81-90/82. Remove Duplicates from Sorted List II.js b/81-90/82. Remove Duplicates from Sorted List II.js
new file mode 100644
index 0000000..da6ff65
--- /dev/null
+++ b/81-90/82. Remove Duplicates from Sorted List II.js	
@@ -0,0 +1,18 @@
+var deleteDuplicates = function(head) {
+    let obj = {}
+    while(head != null){
+        obj[head.val] = (obj[head.val])?obj[head.val]+1:1
+        head = head.next
+    }
+    let a = []
+    for(let c in  obj){
+        if(obj[c] == 1){a.push(c)}
+    }
+    a.sort((a,b)=>{return a-b})
+    let n = new ListNode()
+    let ans = n
+    for(let i = 0 ; i < a.length ; i++){
+        n = n.next = new ListNode(a[i])
+    }
+    return ans.next
+};
\ No newline at end of file
diff --git a/81-90/83. Remove Duplicates from Sorted List.js b/81-90/83. Remove Duplicates from Sorted List.js
new file mode 100644
index 0000000..ef619a4
--- /dev/null
+++ b/81-90/83. Remove Duplicates from Sorted List.js	
@@ -0,0 +1,13 @@
+var deleteDuplicates = function(head) {
+    let a = new Set()
+    let b = new ListNode(0)
+    let c = b
+    while(head != null ){
+        a.add(head.val)
+        head = head.next
+    }
+    for(let x of a){
+        b = b.next = new ListNode(x)
+    }
+    return c.next
+};
\ No newline at end of file
diff --git a/81-90/86. Partition List.js b/81-90/86. Partition List.js
new file mode 100644
index 0000000..52526a7
--- /dev/null
+++ b/81-90/86. Partition List.js	
@@ -0,0 +1,20 @@
+var partition = function(head, x) {
+    if(head === null) return head;
+    const leftDummy = new ListNode(0);
+    const rightDummy = new ListNode(0);
+    let left = leftDummy;
+    let right = rightDummy;
+    while(head){
+    	if(head.val < x) {
+    		left.next = head;
+    		left = head;
+    	} else {
+    		right.next = head;
+    		right = head;
+    	}
+    	head = head.next;
+    }
+    right.next = null;
+    left.next = rightDummy.next;
+    return leftDummy.next;
+};
\ No newline at end of file
diff --git a/81-90/88. Merge Sorted Array.js b/81-90/88. Merge Sorted Array.js
new file mode 100644
index 0000000..5c71551
--- /dev/null
+++ b/81-90/88. Merge Sorted Array.js	
@@ -0,0 +1,9 @@
+var merge = function(nums1, m, nums2, n){
+    nums1.length = m
+    nums2.length = n
+    let ans =  nums1.concat(nums2)
+    ans.sort((a,b)=>a-b)
+    for(let  i = 0 ; i < ans.length ; i++){
+        nums1[i] = ans[i]
+    }
+};
\ No newline at end of file