Generate All Possible Combinations of a String in JavaScript

We are required to write a JavaScript function that takes in a string as the only argument. The function should generate an array of strings that contains all possible contiguous substrings that exist in the array.

Example

Following is the code −

const str = 'Delhi';
const allCombinations = (str1 = '') => {
   const arr = [];
   for (let x = 0, y=1; x < str1.length; x++,y++) {
      arr[x]=str1.substring(x, y);
   };
   const combination = [];
   let temp= "";
   let len = Math.pow(2, arr.length);
   for (let i = 0; i < len ; i++){
      temp= "";
      for (let j=0;j<arr.length;j++) {
         if ((i & Math.pow(2,j))){
            temp += arr[j];
         }
      };
      if (temp !== ""){
         combination.push(temp);
      }
   }
   return combination;
};
console.log(allCombinations(str));

Output

Following is the output on console −

[
   'D', 'e', 'De', 'l',
   'Dl', 'el', 'Del', 'h',
   'Dh', 'eh', 'Deh', 'lh',
   'Dlh', 'elh', 'Delh', 'i',
   'Di', 'ei', 'Dei', 'li',
   'Dli', 'eli', 'Deli', 'hi',
   'Dhi', 'ehi', 'Dehi', 'lhi',
   'Dlhi', 'elhi', 'Delhi'
]