# N-Queens

## What is the N-Queens Problem?

Imagine you have a chessboard and some queens (the most powerful pieces in chess). The N-Queens problem is like a puzzle where you need to place N queens on an N×N chessboard so that **none of them can attack each other**.

### What's a Queen in Chess?

A queen is the strongest piece in chess. She can move:
- **Horizontally** (left and right)
- **Vertically** (up and down)
- **Diagonally** (in any diagonal direction)

She can move as many squares as she wants in these directions!

## The Challenge

Let's say we want to solve the **4-Queens problem** (N=4):
- We have a 4×4 chessboard (16 squares total)
- We need to place 4 queens
- **NO queen can attack any other queen**

### Example: What Does "Attack" Mean?

If we put a queen at position (0,0) - that's the top-left corner - she can attack:

```
Q . . .  ← Queen here attacks all positions marked with X
X . . .
X . . .
X . . .
```

```
Q X X X  ← Queen attacks horizontally
. . . .
. . . .
. . . .
```

```
Q . . .  ← Queen attacks diagonally
. X . .
. . X .
. . . X
```

So we can't put any other queen in any of those X positions!