Add input validation for empty or invalid array in binary search

Backtracking/NQueens.js

@@ -1,8 +1,9 @@
 class NQueens {
   constructor(size) {
-    if (size < 0) {
-      throw RangeError('Invalid board size')
+    if (size <= 0) {
+      throw RangeError('Board size must be a positive integer')
     }
+
     this.board = new Array(size).fill('.').map(() => new Array(size).fill('.'))
     this.size = size
     this.solutionCount = 0
@@ -40,7 +41,7 @@ class NQueens {
   solve(col = 0) {
     if (col >= this.size) {
       this.solutionCount++
-      return true
+      return
     }
 
     for (let i = 0; i < this.size; i++) {
@@ -50,8 +51,6 @@ class NQueens {
         this.removeQueen(i, col)
       }
     }
-
-    return false
   }
 
   printBoard(output = (value) => console.log(value)) {

Search/BinarySearch.js

@@ -8,44 +8,46 @@
  */
 
 function binarySearchRecursive(arr, x, low = 0, high = arr.length - 1) {
+  if (!Array.isArray(arr) || arr.length === 0) {
+    return -1
+  }
+
   const mid = Math.floor(low + (high - low) / 2)
 
   if (high >= low) {
     if (arr[mid] === x) {
-      // item found => return its index
       return mid
     }
 
     if (x < arr[mid]) {
-      // arr[mid] is an upper bound for x, so if x is in arr => low <= x < mid
       return binarySearchRecursive(arr, x, low, mid - 1)
     } else {
-      // arr[mid] is a lower bound for x, so if x is in arr => mid < x <= high
       return binarySearchRecursive(arr, x, mid + 1, high)
     }
-  } else {
-    // if low > high => we have searched the whole array without finding the item
-    return -1
   }
+
+  return -1
 }
+
 function binarySearchIterative(arr, x, low = 0, high = arr.length - 1) {
+  if (!Array.isArray(arr) || arr.length === 0) {
+    return -1
+  }
+
   while (high >= low) {
     const mid = Math.floor(low + (high - low) / 2)
 
     if (arr[mid] === x) {
-      // item found => return its index
       return mid
     }
 
     if (x < arr[mid]) {
-      // arr[mid] is an upper bound for x, so if x is in arr => low <= x < mid
       high = mid - 1
     } else {
-      // arr[mid] is a lower bound for x, so if x is in arr => mid < x <= high
       low = mid + 1
     }
   }
-  // if low > high => we have searched the whole array without finding the item
+
   return -1
 }