From e909e4c5cbd20795d6cb65c525ace084b6566e87 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E9=98=8E=E6=B4=AA=E5=AE=87?= <yhy@credamo.com>
Date: Mon, 22 Aug 2022 01:34:16 +0800
Subject: [PATCH] Tony Yan

Tony Yan completed exercise 2
---
 lib/add.js | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/lib/add.js b/lib/add.js
index 1714b95..542fb18 100644
--- a/lib/add.js
+++ b/lib/add.js
@@ -1,5 +1,16 @@
-function add() {
+function add(a, b) {
   // 实现该函数
+  if (a.length < b.length) [a, b] = [b, a]
+  b = new Array(a.length - b.length).fill('0').join('') + b
+  let carry = 0
+  let nums = []
+  for (let i = a.length - 1; i >= 0; i--) {
+    let num = carry + parseInt(a[i]) + parseInt(b[i])
+    nums.push(num % 10)
+    carry = parseInt(num / 10)
+  }
+  if (carry) nums.push(carry)
+  return nums.reverse().join('')
 }
 
 module.exports = add
\ No newline at end of file