feat(leetcode): ✨ Add answer to median of two sorted arrays

Author: umstek

leetcode/median-of-two-sorted-arrays.ts

@@ -0,0 +1,39 @@
+// This is a O((m+n)/2) solution. It's a bit trickier to code the O(m+n) version.
+
+function findMedianSortedArrays(nums1: number[], nums2: number[]): number {
+  const totalLength = nums1.length + nums2.length;
+  const halfLength = Math.floor(totalLength / 2);
+  // Handle even and odd lengths to indexes: 20 -> 9, 10; 21 -> 10, 10
+  const [targetIndex1, targetIndex2] = [
+    totalLength % 2 === 0 ? halfLength - 1 : halfLength,
+    halfLength,
+  ];
+
+  const arr: number[] = [];
+  let p1 = 0,
+    p2 = 0,
+    n1 = 0,
+    n2 = 0;
+  while (p1 < nums1.length && p2 < nums2.length) {
+    n1 = nums1[p1];
+    n2 = nums2[p2];
+    if (n1 <= n2) {
+      arr.push(n1);
+      p1 += 1;
+    } else {
+      arr.push(n2);
+      p2 += 1;
+    }
+
+    if (arr.length > targetIndex2) {
+      return (arr[targetIndex1] + arr[targetIndex2]) / 2;
+    }
+  }
+
+  if (p1 === nums1.length) {
+    arr.push(...nums2.slice(p2));
+  } else if (p2 === nums2.length) {
+    arr.push(...nums1.slice(p1));
+  }
+  return (arr[targetIndex1] + arr[targetIndex2]) / 2;
+}