Add solution #738

Author: JoshCrozier

README.md

@@ -559,6 +559,7 @@
 733|[Flood Fill](./0733-flood-fill.js)|Easy|
 735|[Asteroid Collision](./0735-asteroid-collision.js)|Medium|
 736|[Parse Lisp Expression](./0736-parse-lisp-expression.js)|Hard|
+738|[Monotone Increasing Digits](./0738-monotone-increasing-digits.js)|Medium|
 739|[Daily Temperatures](./0739-daily-temperatures.js)|Medium|
 743|[Network Delay Time](./0743-network-delay-time.js)|Medium|
 744|[Find Smallest Letter Greater Than Target](./0744-find-smallest-letter-greater-than-target.js)|Easy|

solutions/0738-monotone-increasing-digits.js

@@ -0,0 +1,33 @@
+/**
+ * 738. Monotone Increasing Digits
+ * https://leetcode.com/problems/monotone-increasing-digits/
+ * Difficulty: Medium
+ *
+ * An integer has monotone increasing digits if and only if each pair of adjacent digits
+ * x and y satisfy x <= y.
+ *
+ * Given an integer n, return the largest number that is less than or equal to n with
+ * monotone increasing digits.
+ */
+
+/**
+ * @param {number} n
+ * @return {number}
+ */
+var monotoneIncreasingDigits = function(n) {
+  const digits = String(n).split('').map(Number);
+  let offset = digits.length;
+
+  for (let i = digits.length - 1; i > 0; i--) {
+    if (digits[i - 1] > digits[i]) {
+      offset = i;
+      digits[i - 1]--;
+    }
+  }
+
+  for (let i = offset; i < digits.length; i++) {
+    digits[i] = 9;
+  }
+
+  return +digits.join('');
+};