What is recursive backtracking and can you give me an example?

What is recursive backtracking and can you give me an example?

Recursive backtracking is an algorithmic technique for solving problems incrementally, by trying partial solutions and then abandoning them if they fail to satisfy the conditions of the problem. A classic example is solving a maze.

How does it work in the context of solving a maze?

In a maze, recursive backtracking explores each path from the starting point. If it hits a dead end, it backtracks to the last decision point and tries a different path until it finds the exit.

Can you show me a simple code example of recursive backtracking?

Sure! Here's a simple Python example for solving a maze:

def solve_maze(maze, x, y):
    if (x, y) is the exit:
        return True
    if maze[x][y] is not valid:
        return False
    mark (x, y) as part of the solution
    if solve_maze(maze, x+1, y) or solve_maze(maze, x, y+1):
        return True
    unmark (x, y)
    return False

What are some other applications of recursive backtracking?

Other applications include solving puzzles like Sudoku, generating permutations, and the N-Queens problem.