Improve N-Queens input validation and solution counting clarity

MayankSharma-2812 · MayankSharma-2812 · commit 22399def5e83 · 2026-01-22T11:55:40.000+05:30
diff --git a/Backtracking/NQueens.js b/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)) {

Original file line number	Diff line number	Diff line change
`@@ -1,8 +1,9 @@`
`1`	`1`	`class NQueens {`
`2`	`2`	`constructor(size) {`
`3`		`- if (size < 0) {`
`4`		`- throw RangeError('Invalid board size')`
	`3`	`+ if (size <= 0) {`
	`4`	`+ throw RangeError('Board size must be a positive integer')`
`5`	`5`	`}`
	`6`	`+`
`6`	`7`	`this.board = new Array(size).fill('.').map(() => new Array(size).fill('.'))`
`7`	`8`	`this.size = size`
`8`	`9`	`this.solutionCount = 0`
`@@ -40,7 +41,7 @@ class NQueens {`
`40`	`41`	`solve(col = 0) {`
`41`	`42`	`if (col >= this.size) {`
`42`	`43`	`this.solutionCount++`
`43`		`- return true`
	`44`	`+ return`
`44`	`45`	`}`
`45`	`46`
`46`	`47`	`for (let i = 0; i < this.size; i++) {`
`@@ -50,8 +51,6 @@ class NQueens {`
`50`	`51`	`this.removeQueen(i, col)`
`51`	`52`	`}`
`52`	`53`	`}`
`53`		`-`
`54`		`- return false`
`55`	`54`	`}`
`56`	`55`
`57`	`56`	`printBoard(output = (value) => console.log(value)) {`