4x Puzzle

4x Puzzle is a classic number sliding puzzle game, also known as the 15-Puzzle. You need to slide number tiles in a 4×4 grid to arrange them in order and complete the puzzle.

Game Rules:

• 4×4 grid has 15 number tiles (1-15) and one blank space
• Number tiles can slide to adjacent blank spaces
• Goal is to arrange numbers in 1-2-3-4... order
• Blank space should be in the bottom-right corner when complete

Controls:

• Click number tiles adjacent to blank space to move them
• Can also use keyboard arrow keys
• Can only move toward blank space, no diagonal moves

Solving Strategy:

• Row by row: Solve first row first, then second row
• Circular moves: Use blank space to create movement space
• Corners first: Corner tiles are relatively fixed, solve them first
• Last two rows: Need special technique to solve together

Solution Technique:

1. Place numbers 1 and 2 in first two positions of row 1
2. Place numbers 3 and 4 in last two positions of row 1
3. Complete row 2 the same way
4. Handle last two rows together using circular moves

Difficulty Levels:

• Easy: Numbers close to completed state
• Medium: Requires more moves to solve
• Hard: Random shuffle, needs complete strategy

Tips:

• Don't move randomly, every move should have purpose
• Imagine final positions of numbers, work backwards
• Use blank space as a "transit station"
• Be patient, complex situations need many steps planned ahead