Как найти самую длинную строку в массиве

Is there a short way to find the longest string in a string array?

Something like arr.Max(x => x.Length);?

function max( input ) {
return input.reduce((a, b) => a.length <= b.length ? b : a)
}

answered Nov 25, 2021 at 20:07

I was inspired of Jason’s function and made a little improvements to it and got as a result rather fast finder:

function timo_longest(a) {
  var c = 0, d = 0, l = 0, i = a.length;
  if (i) while (i--) {
    d = a[i].length;
    if (d > c) {
      l = i; c = d;
    }
  }
  return a[l];
}
arr=["First", "Second", "Third"];
var longest = timo_longest(arr);

Speed results: http://jsperf.com/longest-string-in-array/7

answered Sep 23, 2012 at 0:52

If your string is already split into an array, you’ll not need the split part.

function findLongestWord(str) {
  str = str.split(' ');
  var longest = 0;

  for(var i = 0; i < str.length; i++) {
     if(str[i].length >= longest) {
       longest = str[i].length;
        } 
     }
  return longest;
}
findLongestWord("The quick brown fox jumped over the lazy dog");

answered Nov 21, 2017 at 3:19

In case you expect more than one maximum this will work:

_.maxBy(Object.entries(_.groupBy(x, y => y.length)), y => parseInt(y[0]))[1]

It uses lodash and returns an array.

answered Mar 13, 2018 at 18:27

With ES6 and it support a duplicate string

var allLongestStrings = arrayOfStrings => {
  let maxLng = Math.max(...arrayOfStrings.map( elem => elem.length))
  return arrayOfStrings.filter(elem => elem.length === maxLng)
}

let arrayOfStrings = ["aba", "aa", "ad", "vcd","aba"]
 
console.log(allLongestStrings(arrayOfStrings))

answered Aug 6, 2018 at 20:52

I would do something like this:

function findLongestWord(str) {
   var array = str.split(" ");
   var maxLength=array[0].length;
   for(var i=0; i < array.length; i++ ) {
      if(array[i].length > maxLength) maxLength = array[i].length
   }
 return maxLength;
}

findLongestWord("What if we try a super-long word such as otorhinolaryngology");

answered Dec 26, 2015 at 10:58

Modern browsers support a for...of loop. The fastest and shortest way to solve this problem in Chrome, Safari, Edge, and Firefox is also the clearest:

let largest = '';
for (let item of arr) {
  if (item.length > largest.length) largest = item
}

In IE, you can use Array.forEach; that’s still faster and clearer than sorting or reducing the array.

var largest = '';
arr.forEach(function(item) {
  if (item.length > largest.length) largest = item
});

answered Apr 3, 2020 at 6:06

If you want to know the INDEX of the longest item:

var longest = arr.reduce(
        (a, b, i) => arr[a].length < b.length ? i : a,
        0
    );

(which can be a one-liner for those that love that stuff…. but it’s split up here for readabilty)

answered Feb 21, 2022 at 21:54