Check if a string is sorted in JavaScript

We are required to write a JavaScript function that takes in a string and checks whether it is sorted or not.

For example −

isSorted('adefgjmxz')  // true isSorted('zxmfdba')     // true isSorted('dsfdsfva')     // false

Example

Following is the code −

const str = 'abdfhlmxz'; const findDiff = (a, b) => a.charCodeAt(0) - b.charCodeAt(0); const isStringSorted = (str = '') => {    if(str.length < 2){       return true;    };    let res = ''    for(let i = 0; i < str.length-1; i++){       if(findDiff(str[i+1], str[i]) > 0){          res += 'u';       }else if(findDiff(str[i+1], str[i]) < 0){          res += 'd';       };       if(res.indexOf('u') && res.includes('d')){          return false;       };    };    return true; }; console.log(isStringSorted(str));

Output

This will produce the following output in console −

true