java-basics/java-programs/Permutation.java at master · Sethu1910/java-basics · GitHub

31 lines (27 loc) · 791 Bytes

package misc;

/**

* Algorithm:-

* 1. Try each of the letters in turn as the first letter and

* then find all the permutations of the remaining letters using a recursive call.

* 2. The base case is when the input is an empty string the only permutation is the empty string.

public class Permutation {

public static void permutation(String str) {

permutation("", str);

}

private static void permutation(String prefix, String str) {

int n = str.length();

if (n == 0)

System.out.println(prefix);

else {

for (int i = 0; i < n; i++)

permutation(prefix + str.charAt(i), str.substring(0, i) + str.substring(i + 1, n));

}

public static void main(String[] args) {

String str = "ABC";

Permutation obj = new Permutation();

obj.permutation(str);

}

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