What are some common recursion techniques in Java?

What are some common recursion techniques in Java?

Common recursion techniques in Java include direct recursion, indirect recursion, tail recursion, and backtracking.

Can you explain tail recursion with an example?

Sure! Tail recursion occurs when the recursive call is the last operation in the function. For example:

int factorial(int n, int accumulator) {
    if (n == 0) return accumulator;
    return factorial(n - 1, n * accumulator);
}

This function calculates the factorial using tail recursion.

What is backtracking in recursion?

Backtracking is a technique for solving problems incrementally, trying partial solutions and then abandoning them if they don't lead to a valid solution. It's often used in puzzles and combinatorial problems.

Can you give an example of backtracking in Java?

Certainly! Here's a simple example of backtracking to solve the N-Queens problem:

public class NQueens {
    public void solveNQueens(int n) {
        // Implementation of backtracking algorithm
    }
}

This method would place N queens on an N×N chessboard such that no two queens threaten each other.