<pre class="shiki github-dark shaku"><code>type EntityBase = { indices: [number, number]}type UrlEntity = EntityBase &amp; { displayUrl: string, url: string,}type MentionEntity = EntityBase &amp; { screeName: string}type MixedEntity = UrlEntity | MentionEntitytype Entities = { urls: Array&lt;UrlEntity&gt;, mentions: Array&lt;MentionEntity&gt;}function replaceStringByIndices(str: string, start: number, end: number, newStr: string): string { let arr = str.split(''); arr.splice(start, end - start, newStr); return arr.join('');}function renderTextWithEntities(text: string, entities: Entities): string { // put your code here // The core is to recalculate the indices after each replacement let n: number = text.length; let mixed: UrlEntity[] = entities.urls; for (let mention of entities.mentions) { let urlEntity: UrlEntity = { url: `https://x.com/${mention.screeName}`, displayUrl: `@${mention.screeName}`, indices: mention.indices }; mixed.push(urlEntity); } // sort the items by indices mixed.sort((a, b) =&gt; a.indices[0] - b.indices[0]); console.log(`mixed: ${mixed}`) let tempStr: string = text; let offset: number = 0; for (let item of mixed) { let newStr = `&lt;a href="${item.url}"&gt;${item.displayUrl}&lt;/a&gt;` tempStr = replaceStringByIndices(tempStr, item.indices[0] + offset, item.indices[1] + offset, newStr); offset += newStr.length - (item.indices[1] - item.indices[0]); } return tempStr;}</code></pre>

Use offset and sort to solve the problem in O(n) time complexity

On Twitter(now X), we always see mentions, hashtags and links in blue links, like this one below. > Shaku syntax is now supported on https://t.co/Upkm…