Find all substring of a given string in O(n^2) time.

function genSubstrings(inputString){    debugger;    let resultArray = [];    // outer loop to run n times [n = size of string]    for(let i = 0; i < inputString.length; i++){        // pushing first char of string as substring        // as we know that each char will be substring itself too.        resultArray.push(inputString[i]);        // inner loop to run n - 1 times;        for(let j = i + 1; j < inputString.length; j++){            // get last substring and append the new next char            resultArray.push(              resultArray[resultArray.length - 1] + inputString[j]            );        }    }    return resultArray;}

genSubstrings("abcd");(10)['a', 'ab', 'abc', 'abcd', 'b', 'bc', 'bcd', 'c', 'cd', 'd']