Add solution #807

JoshCrozier · JoshCrozier · commit 46122ba37c94 · 2025-04-20T14:52:11.000-05:00
diff --git a/README.md b/README.md
@@ -1,4 +1,4 @@
-# 1,391 LeetCode solutions in JavaScript
+# 1,392 LeetCode solutions in JavaScript
 
 [https://leetcodejavascript.com](https://leetcodejavascript.com)
 
@@ -620,6 +620,7 @@
 804|[Unique Morse Code Words](./solutions/0804-unique-morse-code-words.js)|Easy|
 805|[Split Array With Same Average](./solutions/0805-split-array-with-same-average.js)|Hard|
 806|[Number of Lines To Write String](./solutions/0806-number-of-lines-to-write-string.js)|Easy|
+807|[Max Increase to Keep City Skyline](./solutions/0807-max-increase-to-keep-city-skyline.js)|Medium|
 808|[Soup Servings](./solutions/0808-soup-servings.js)|Medium|
 809|[Expressive Words](./solutions/0809-expressive-words.js)|Medium|
 810|[Chalkboard XOR Game](./solutions/0810-chalkboard-xor-game.js)|Hard|
diff --git a/solutions/0807-max-increase-to-keep-city-skyline.js b/solutions/0807-max-increase-to-keep-city-skyline.js
@@ -0,0 +1,46 @@
+/**
+ * 807. Max Increase to Keep City Skyline
+ * https://leetcode.com/problems/max-increase-to-keep-city-skyline/
+ * Difficulty: Medium
+ *
+ * There is a city composed of n x n blocks, where each block contains a single building shaped
+ * like a vertical square prism. You are given a 0-indexed n x n integer matrix grid where
+ * grid[r][c] represents the height of the building located in the block at row r and column c.
+ *
+ * A city's skyline is the outer contour formed by all the building when viewing the side of the
+ * city from a distance. The skyline from each cardinal direction north, east, south, and west
+ * may be different.
+ *
+ * We are allowed to increase the height of any number of buildings by any amount (the amount can
+ * be different per building). The height of a 0-height building can also be increased. However,
+ * increasing the height of a building should not affect the city's skyline from any cardinal
+ * direction.
+ *
+ * Return the maximum total sum that the height of the buildings can be increased by without
+ * changing the city's skyline from any cardinal direction.
+ */
+
+/**
+ * @param {number[][]} grid
+ * @return {number}
+ */
+var maxIncreaseKeepingSkyline = function(grid) {
+  let result = 0;
+  const rowMaxes = grid.map(row => Math.max(...row));
+  const columnMaxes = grid.map((row, index) => grid.map(row => row[index]))
+    .map(row => Math.max(...row));
+
+  for (let i = 0; i < grid.length; i++) {
+    for (let j = 0; j < grid[i].length; j++) {
+      const currentHeight = grid[i][j];
+      const minHeight = Math.min(
+        Math.max(rowMaxes[i], currentHeight),
+        Math.max(columnMaxes[j], currentHeight)
+      );
+
+      result += (minHeight - currentHeight);
+    }
+  }
+
+  return result;
+};
