diff --git a/lab4/1.js b/lab4/1.js
index c7c43cf..b2db97c 100644
--- a/lab4/1.js
+++ b/lab4/1.js
@@ -6,7 +6,13 @@
  * ['мир', 'Рим', 'сирота', 'Ариост', 'мри', 'пва', 'лор', 'авп']; -> [["мир", "Рим", "мри"], ["сирота", "Ариост"], ["пва", "авп"]]
  */
 function getAnagramms(arr) {
-    //code here
+    let groups = {};
+    arr.map( function(word) {
+        let key = word.toLowerCase().split('').sort();
+        groups[key] ? groups[key].push(word) : groups[key] = [word];
+    } );
+    return Object.values(groups);
 }
 
 module.exports = getAnagramms;
+console.log(getAnagramms(['мир', 'Рим', 'сирота', 'Ариост', 'мри', 'пва', 'лор', 'авп']));
diff --git a/lab4/2.js b/lab4/2.js
index 9c1abc1..0b9937d 100644
--- a/lab4/2.js
+++ b/lab4/2.js
@@ -7,7 +7,7 @@
  * "тот" -> true
  */
 function isPalindrome(str) {
-    //code here
+    return str.split('').join() === str.split('').reverse().join();
 }
 
 module.exports = isPalindrome;
diff --git a/lab4/3.js b/lab4/3.js
index a65bef0..c9bcacf 100644
--- a/lab4/3.js
+++ b/lab4/3.js
@@ -8,7 +8,17 @@
  */
 
 function rle(str) {
-    //code here
+    return str.split('').reduce( function(result, value, index, arr) {
+        if (result[result.length - 2] === value) {
+            result[result.length - 1] = result[result.length - 1] + 1;
+            return result;
+        }
+        if (result[result.length - 1] < 2) result.pop();
+        result.push(value);
+        if (index != arr.length - 1) result.push(1);
+        return result;
+    }, []).join('');
 }
 
 module.exports = rle;
+console.log(rle('BCCADDEEEBB'));
\ No newline at end of file
diff --git a/lab4/4.js b/lab4/4.js
index 7d6162e..06361bd 100644
--- a/lab4/4.js
+++ b/lab4/4.js
@@ -17,7 +17,18 @@
 */
 
 function get1DArray(arr) {
-    //code here
+    return arr.flat(Infinity);
 }
 
 module.exports = get1DArray;
+console.log(get1DArray([1, 2, 'aa', [1, 2, 3],
+[
+    [1, 2],
+    [1, 2]
+],
+[
+    [
+        [1, 2, [1, 2, [2]]], 3
+    ], 4
+]
+]));
\ No newline at end of file
diff --git a/lab4/5.js b/lab4/5.js
index 4760146..8dd4419 100644
--- a/lab4/5.js
+++ b/lab4/5.js
@@ -11,7 +11,18 @@
  */
 
 function checkBrackets(str) {
-    //code here
+    if (str.length % 2) return false;
+    let queue = [];
+    for (elem of str) {
+        if ('[(<'.includes(elem)) {
+            queue.push(elem === '[' ? ']' : elem === '(' ? ')' : '>');
+            continue;
+        }
+        elem === queue[queue.length - 1] ? queue.pop() : elem = '';
+        if (!elem) return false;
+    }
+    return true;
 }
 
 module.exports = checkBrackets;
+console.log(checkBrackets('[(()[])<(<>)>]'));
diff --git a/tests/lab4.test.js b/tests/lab4.test.js
index 439a487..236f1a1 100644
--- a/tests/lab4.test.js
+++ b/tests/lab4.test.js
@@ -71,18 +71,18 @@ test("get1DArray 2", () => {
     expect(get1DArray([])).toEqual([]);
 });
 
-// test('checkBrackets 1', () => {
-//     expect(checkBrackets('[(<>)]')).toBe(true);
-// });
-// test('checkBrackets 2', () => {
-//     expect(checkBrackets('([)]()<>')).toBe(false);
-// });
-// test('checkBrackets 3', () => {
-//     expect(checkBrackets('[[()]]([])<>')).toBe(true);
-// });
-// test('checkBrackets 4', () => {
-//     expect(checkBrackets('[]')).toBe(true);
-// });
-// test('checkBrackets 5', () => {
-//     expect(checkBrackets('')).toBe(true);
-// });
+test('checkBrackets 1', () => {
+    expect(checkBrackets('[(<>)]')).toBe(true);
+});
+test('checkBrackets 2', () => {
+    expect(checkBrackets('([)]()<>')).toBe(false);
+});
+test('checkBrackets 3', () => {
+    expect(checkBrackets('[[()]]([])<>')).toBe(true);
+});
+test('checkBrackets 4', () => {
+    expect(checkBrackets('[]')).toBe(true);
+});
+test('checkBrackets 5', () => {
+    expect(checkBrackets('')).toBe(true);
+});