finish 0067

Author: benben6515

README.md

@@ -30,6 +30,7 @@ since 2021.10.10 / Benben
 - 0035.Search Insert Position
 - 0053.Maximum SubArray
 - 0058.Length of Last Word
+- 0067.Add Binary
 - 0104.Maximum Depth of Binary Tree
 - 0100.Same Tree
 - 0110.Balanced Binary Tree

leetcode-easy/0067-add-binary.js

@@ -0,0 +1,43 @@
+/**
+ * @param {string} a
+ * @param {string} b
+ * @return {string}
+ */
+var addBinary = function(a, b) {
+  if (a.length < b.length) return addBinary(b, a)
+  const arrA = a.split('').reverse()
+  const arrB = b.split('').reverse()
+  let curry = 0
+  let sum = 0
+
+  arrA.forEach((e, i) => {
+    let numB = 0
+    if (i < arrB.length) numB = +(arrB[i])
+    sum = curry + (+e) + numB
+    switch (sum) {
+      case 0:
+        arrA[i] = '0'
+        curry = 0
+        break
+      case 1:
+        arrA[i] = '1'
+        curry = 0
+        break
+      case 2:
+        arrA[i] = '0'
+        curry = 1
+        break
+      case 3:
+        arrA[i] = '1'
+        curry = 1
+        break
+    }
+  })
+
+  if (curry) arrA.push('1')
+  return arrA.reverse().join('')
+};
+
+// 2022/06/13 done.
+// Runtime: 105 ms, faster than 28.95% of JavaScript online submissions for Add Binary.
+// Memory Usage: 42.6 MB, less than 80.31% of JavaScript online submissions for Add Binary.