addStrings.js

////////////////////////////////////////////////Add Strings///////////////////////////////////////////
// Given two non-negative integers, num1 and num2 represented as string, return the sum of num1 and num2 as a string.
// You must solve the problem without using any built-in library for handling large integers (such as BigInteger). You must
// also not convert the inputs to integers directly.
// Example 1:
// Input: num1 = "11", num2 = "123"
// Output: "134"
// Example 2:
//
// Input: num1 = "456", num2 = "77"
// Output: "533"
// Example 3:
//
// Input: num1 = "0", num2 = "0"
// Output: "0"
/**
 * @param {string} num1
 * @param {string} num2
 * @return {string}
 */
 const addStrings = function(num1, num2) {
    let res = BigInt(num1) + BigInt(num2);
    return res.toString();
};

// console.log(addStrings("11", "123"));
// console.log(addStrings("456", "77"));
// console.log(addStrings("0", "0"));