Javascript
ΠΠΎ Π²ΡΠ΅ΠΌ Π²ΠΎΠΏΡΠΎΡΠ°ΠΌ - @workakkk @itchannels_telegram -π₯Π»ΡΡΡΠΈΠ΅ ΠΠ’-ΠΊΠ°Π½Π°Π»Ρ @ai_machinelearning_big_data - ΠΌΠ°ΡΠΈΠ½Π½ΠΎΠ΅ ΠΎΠ±ΡΡΠ΅Π½ΠΈΠ΅ @JavaScript_testit- js ΡΠ΅ΡΡΡ @pythonl - π @ArtificialIntelligencedl - AI @datascienceiot - ml π Π ΠΠ: β 5153160945
Show moreπ Analytical overview of Telegram channel Javascript
Channel Javascript (@javascriptv) in the Russian language segment is an active participant. Currently, the community unites 17 173 subscribers, ranking 7 380 in the Technologies & Applications category and 38 243 in the Russia region.
π Audience metrics and dynamics
Since its creation on Π½Π΅Π²ΡΠ΄ΠΎΠΌΠΎ, the project has demonstrated rapid growth, gathering an audience of 17 173 subscribers.
According to the latest data from 30 August, 2026, the channel demonstrates stable activity. Although there has been a change in the number of participants by -128 over the last 30 days and by 0 over the last 24 hours, overall reach remains high.
- Verification status: Not verified
- Engagement rate (ER): The average audience engagement rate is 28.47%. Within the first 24 hours after publication, content typically collects 5.25% reactions from the total number of subscribers.
- Post reach: On average, each post receives 4 891 views. Within the first day, a publication typically gains 902 views.
- Reactions and interaction: The audience actively supports content: the average number of reactions per post is 15.
- Thematic interests: Content is focused on key topics such as javascript, github, Π±ΠΈΡΡΠΈΠΊΡ24, api, css.
π Description and content policy
The author describes the resource as a platform for expressing subjective opinions:
βΠΠΎ Π²ΡΠ΅ΠΌ Π²ΠΎΠΏΡΠΎΡΠ°ΠΌ - @workakkk
@itchannels_telegram -π₯Π»ΡΡΡΠΈΠ΅ ΠΠ’-ΠΊΠ°Π½Π°Π»Ρ
@ai_machinelearning_big_data - ΠΌΠ°ΡΠΈΠ½Π½ΠΎΠ΅ ΠΎΠ±ΡΡΠ΅Π½ΠΈΠ΅
@JavaScript_testit- js ΡΠ΅ΡΡΡ
@pythonl - π
@ArtificialIntelligencedl - AI
@datascienceiot - ml π
Π ΠΠ: β 5153160945β
Thanks to the high frequency of updates (latest data received on 31 August, 2026), the channel maintains relevance and a high level of publication reach. Analytics show that the audience actively interacts with content, making it an important point of influence in the Technologies & Applications category.
const array = [{a: 1, b: 1}, {a: 2, b: 2}, {a: 3, b: 3}, {a: 4, b: 4}]
console.log(array.findLast(n => n)); //result -> {a: 4,b: 4 }
console.log(array.findLast(n => n.a * 5 === 20)); // result -> {a:4,b:4} as the condition is true so it returns the last element.
console.log(array.findLast(n => n.a * 5 === 21)); //result -> undefined as the condition is false so return undefined instead of {a:4,b:4}.
console.log(array.findLastIndex(n => n.a * 5 === 21)); // result -> -1 as the condition is not justified for returning the last element.
console.log(array.findLastIndex(n => n.a * 5 === 20)); // result -> 3 which is the index of the last element as the condition is true.
2. ΠΡΠ°ΠΌΠΌΠ°ΡΠΈΠΊΠ° Hashbang
ΠΡΠ° ΡΡΠ½ΠΊΡΠΈΡ ΠΏΠΎΠ·Π²ΠΎΠ»ΠΈΡ Π½Π°ΠΌ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°ΡΡ Hashbang/Shebang Π² Π½Π΅ΠΊΠΎΡΠΎΡΡΡ
CLI.
Shebang ΠΏΡΠ΅Π΄ΡΡΠ°Π²Π»Π΅Π½ #! ΠΈ ΠΏΡΠ΅Π΄ΡΡΠ°Π²Π»ΡΠ΅Ρ ΡΠΎΠ±ΠΎΠΉ ΡΠΏΠ΅ΡΠΈΠ°Π»ΡΠ½ΡΡ ΡΡΡΠΎΠΊΡ Π² Π½Π°ΡΠ°Π»Π΅ ΡΠΊΡΠΈΠΏΡΠ°, ΠΊΠΎΡΠΎΡΠ°Ρ ΡΠΎΠΎΠ±ΡΠ°Π΅Ρ ΠΎΠΏΠ΅ΡΠ°ΡΠΈΠΎΠ½Π½ΠΎΠΉ ΡΠΈΡΡΠ΅ΠΌΠ΅, ΠΊΠ°ΠΊΠΎΠΉ ΠΈΠ½ΡΠ΅ΡΠΏΡΠ΅ΡΠ°ΡΠΎΡ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°ΡΡ ΠΏΡΠΈ Π²ΡΠΏΠΎΠ»Π½Π΅Π½ΠΈΠΈ ΡΠΊΡΠΈΠΏΡΠ°.
#!/usr/bin/env node
// in the Script Goal
'use strict';
console.log(2*3);
#!/usr/bin/env node
// in the Module Goal
export {};
console.log(2*2);
Π‘ΡΡΠΎΠΊΠ° #!/usr/bin/env node Π²ΡΠ·ΡΠ²Π°Π΅Ρ ΠΈΡΡ
ΠΎΠ΄Π½ΡΠΉ ΡΠ°ΠΉΠ» Node.js Π½Π°ΠΏΡΡΠΌΡΡ ΠΊΠ°ΠΊ ΠΈΡΠΏΠΎΠ»Π½ΡΠ΅ΠΌΡΠΉ ΡΠ°ΠΉΠ».
3. Π‘ΠΈΠΌΠ²ΠΎΠ»Ρ-ΠΊΠ»ΡΡΠΈ Π² WeakMap
Π’Π΅ΠΏΠ΅ΡΡ ΠΌΠΎΠΆΠ½ΠΎ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°ΡΡ ΡΠ½ΠΈΠΊΠ°Π»ΡΠ½ΡΠ΅ ΡΠΈΠΌΠ²ΠΎΠ»Ρ Π² ΠΊΠ°ΡΠ΅ΡΡΠ²Π΅ ΠΊΠ»ΡΡΠ΅ΠΉ.
ΠΠΎ ΡΡΠΎΠ³ΠΎ ΠΎΠ±Π½ΠΎΠ²Π»Π΅Π½ΠΈΡ WeakMaps ΠΌΠΎΠΆΠ½ΠΎ Π±ΡΠ»ΠΎ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°ΡΡ Π² ΠΊΠ°ΡΠ΅ΡΡΠ²Π΅ ΠΊΠ»ΡΡΠ΅ΠΉ ΡΠΎΠ»ΡΠΊΠΎ ΠΎΠ±ΡΠ΅ΠΊΡΡ. ΠΠ±ΡΠ΅ΠΊΡΡ ΠΈΡΠΏΠΎΠ»ΡΠ·ΡΡΡΡΡ Π² ΠΊΠ°ΡΠ΅ΡΡΠ²Π΅ ΠΊΠ»ΡΡΠ΅ΠΉ Π΄Π»Ρ WeakMaps, ΠΏΠΎΡΠΎΠΌΡ ΡΡΠΎ ΠΎΠ½ΠΈ ΠΈΠΌΠ΅ΡΡ ΠΎΠ΄ΠΈΠ½ ΠΈ ΡΠΎΡ ΠΆΠ΅ Π°ΡΠΏΠ΅ΠΊΡ ΠΈΠ΄Π΅Π½ΡΠΈΡΠ½ΠΎΡΡΠΈ.
Symbol β ΡΡΠΎ Π΅Π΄ΠΈΠ½ΡΡΠ²Π΅Π½Π½ΡΠΉ ΠΏΡΠΈΠΌΠΈΡΠΈΠ²Π½ΡΠΉ ΡΠΈΠΏ Π² ECMAScript, ΠΊΠΎΡΠΎΡΡΠΉ ΠΏΠΎΠ·Π²ΠΎΠ»ΡΠ΅Ρ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°ΡΡ Π΄Π»Ρ Π½Π΅Π³ΠΎ ΡΠ½ΠΈΠΊΠ°Π»ΡΠ½ΡΠ΅ Π·Π½Π°ΡΠ΅Π½ΠΈΡ. ΠΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°ΡΡ Symbol ΡΠ΅ΠΏΠ΅ΡΡ ΠΌΠΎΠΆΠ½ΠΎ ΠΈ Π² ΠΊΠ°ΡΠ΅ΡΡΠ²Π΅ ΠΊΠ»ΡΡΠ° Π²ΠΌΠ΅ΡΡΠΎ ΡΠΎΠ·Π΄Π°Π½ΠΈΡ Π½ΠΎΠ²ΠΎΠ³ΠΎ ΠΎΠ±ΡΠ΅ΠΊΡΠ° Ρ ΠΏΠΎΠΌΠΎΡΡΡ WeakMap.
const weak = new WeakMap();
const key = Symbol('my ref');
const someObject = { a:1 };
weak.set(key, someObject);
console.log(weak.get(key));
4. ΠΠ·ΠΌΠ΅Π½ΠΈΡΡ ΠΌΠ°ΡΡΠΈΠ² ΡΠ΅ΡΠ΅Π· ΠΊΠΎΠΏΠΈΡΠΎΠ²Π°Π½ΠΈΠ΅
ΠΠ±Π½ΠΎΠ²Π»Π΅Π½ΠΈΠ΅ ΠΏΡΠ΅Π΄ΠΎΡΡΠ°Π²Π»ΡΠ΅Ρ Π΄ΠΎΠΏΠΎΠ»Π½ΠΈΡΠ΅Π»ΡΠ½ΡΠ΅ ΠΌΠ΅ΡΠΎΠ΄Ρ Π² Array.prototype Π΄Π»Ρ Π²Π½Π΅ΡΠ΅Π½ΠΈΡ ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΠΉ Π² ΠΌΠ°ΡΡΠΈΠ², Π²ΠΎΠ·Π²ΡΠ°ΡΠ°Ρ Π΅Π³ΠΎ Π½ΠΎΠ²ΡΡ ΠΊΠΎΠΏΠΈΡ Ρ ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ΠΌ Π²ΠΌΠ΅ΡΡΠΎ ΠΎΠ±Π½ΠΎΠ²Π»Π΅Π½ΠΈΡ ΠΈΡΡ
ΠΎΠ΄Π½ΠΎΠ³ΠΎ ΠΌΠ°ΡΡΠΈΠ²Π°.
ΠΠΎΠ²ΡΠ΅ Π²Π²Π΅Π΄Π΅Π½Π½ΡΠ΅ ΡΡΠ½ΠΊΡΠΈΠΈ Array.prototype:
Array.prototype.toReversed()
Array.prototype.toSorted(compareFn)
Array.prototype.toSpliced (start, deleteCount, β¦ items)
Array.prototype.with(index, value)
const numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9]
/* toReversed */
const reversed = numbers.toReversed();
console.log("reversed", reversed); // "reversed", [9, 8, 7, 6, 5, 4, 3, 2, 1]
console.log("original", numbers); // "original", [1, 2, 3, 4, 5, 6, 7, 8, 9]
/* toSorted */
const sortedArr = numbers.toSorted();
console.log("sorted", sortedArr); // "sorted", [1, 2, 3, 4, 5, 6, 7, 8, 9]
console.log("original", numbers); // "original", [1, 2, 3, 4, 5, 6, 7, 8, 9]
/* with */
const replaceWith = numbers.with(1, 100);
console.log("with", replaceWith); // "with", [1, 100, 3, 4, 5, 6, 7, 8, 9]
console.log("original", numbers); // "original", [1, 2, 3, 4, 5, 6, 7, 8, 9]
/* toSpliced */
const splicedArr = numbers.toSpliced(0, 4);
console.log("toSpliced", splicedArr); // "toSpliced", [5, 6, 7, 8, 9]
console.log("original", numbers); // "original", [1, 2, 3, 4, 5, 6, 7, 8, 9]
@javascriptvDate() Π² JavaScript Π±ΡΠ»Π° ΡΠΊΠΎΠΏΠΈΡΠΎΠ²Π°Π½Π° Π½Π΅ΠΏΠΎΡΡΠ΅Π΄ΡΡΠ²Π΅Π½Π½ΠΎ ΠΈΠ· Java Π² 1995 Π³ΠΎΠ΄Ρ. ΠΠ²Π° Π³ΠΎΠ΄Π° ΡΠΏΡΡΡΡ Java ΠΎΡΠΊΠ°Π·Π°Π»Π°ΡΡ ΠΎΡ Π½Π΅Ρ, Π½ΠΎ Π² JavaScript ΠΎΠ½Π° ΠΎΡΡΠ°Π»Π°ΡΡ Π΄Π»Ρ ΠΎΠ±ΡΠ°ΡΠ½ΠΎΠΉ ΡΠΎΠ²ΠΌΠ΅ΡΡΠΈΠΌΠΎΡΡΠΈ. ΠΡΠΈ ΡΡΠΎΠΌ Date() ΠΊΡΠ°ΠΉΠ½Π΅ Π½Π΅ΡΠ΄ΠΎΠ±Π΅Π½ ΠΈ ΡΠ°ΡΡΠΎ Π½Π΅ΠΏΡΠ΅Π΄ΡΠΊΠ°Π·ΡΠ΅ΠΌ, Π° API ΠΎΡΡΠ°Π²Π»ΡΠ΅Ρ ΠΆΠ΅Π»Π°ΡΡ Π»ΡΡΡΠ΅Π³ΠΎ.
Π ΡΡΠ°ΡΡΡΡ, Π΅ΡΡΡ Temporal API, ΠΊΠΎΡΠΎΡΠΎΠ΅ ΡΠ΅ΡΠ°Π΅Ρ ΡΡΡ ΠΏΡΠΎΠ±Π»Π΅ΠΌΡ. ΠΠΎΠ΄ΡΠΎΠ±Π½Π΅Π΅ ΠΎ Π½ΡΠΌ:
https://webdevblog.ru/vvedenie-v-javascript-temporal-api/
#javascript/**
* @param {number[]} nums
* @param {number} target
* @return {number}
*/
var threeSumClosest = function(nums, target) {
nums.sort((a,b)=>a-b);
let closest = Infinity;
for (let i=0;i<nums.length-2;i++) {
let left = i+1; right = nums.length-1;
while (left < right) {
let localSum = nums[i] + nums[left] + nums[right];
if (Math.abs(localSum - target) < Math.abs(closest - target)) closest = localSum;
if (localSum > target) right--;
else left++;
}
}
return closest;
};
ΠΠΈΡΠΈΡΠ΅ ΡΠ²ΠΎΠ΅ ΡΠ΅ΡΠ΅Π½ΠΈΠ΅ Π² ΠΊΠΎΠΌΠΌΠ΅Π½ΡΠ°ΡΠΈΡΡ
π
@javascriptv// Time complexity: O(n)
// Space complexity: O(n)
var goodNodes = function(root) {
let count = 0;
function dfs(root, max) {
if (root == null)
return;
if (root.val >= max) {
max = root.val;
count++;
}
dfs(root.left, max);
dfs(root.right, max);
}
dfs(root, root.val);
return count;
};
ΠΠΈΡΠΈΡΠ΅ ΡΠ²ΠΎΠ΅ ΡΠ΅ΡΠ΅Π½ΠΈΠ΅ Π² ΠΊΠΎΠΌΠΌΠ΅Π½ΡΠ°ΡΠΈΡΡ
π
@javascriptv-------------------------- -----
[1 3 -1] -3 5 3 6 7 3
1 [3 -1 -3] 5 3 6 7 3
1 3 [-1 -3 5] 3 6 7 5
1 3 -1 [-3 5 3] 6 7 5
1 3 -1 -3 [5 3 6] 7 6
1 3 -1 -3 5 [3 6 7] 7
ΠΠ²ΠΎΠ΄: nums = [1], k = 1
ΠΡΠ²ΠΎΠ΄: [1]
Π Π΅ΡΠ΅Π½ΠΈΠ΅
ΠΠΈΡΠΈΡΠ΅ ΡΠ²ΠΎΠ΅ ΡΠ΅ΡΠ΅Π½ΠΈΠ΅ Π² ΠΊΠΎΠΌΠΌΠ΅Π½ΡΠ°ΡΠΈΡΡ
π
@javascriptv