prints all permutations of given character array/ string, with swap

Author: NirmalSilwal

CodingBlocks Training/Day12/PermutationWithSwap.java

@@ -0,0 +1,45 @@
+package Lecture12;
+
+public class PermutationWithSwap {
+
+	public static void main(String[] args) {
+
+		char[] arr = { 'a', 'b', 'c' };
+		int front = 0, back = arr.length - 1;
+		printPermutation(arr, front, back);
+	}
+
+	public static void printPermutation(char[] arr, int front, int back) {
+		if (front > back) {
+			display(arr);
+		}
+		for (int i = front; i < arr.length; i++) {
+			swap(arr, front, i);
+			printPermutation(arr, front + 1, back);
+			swap(arr, front, i);
+		}
+	}
+
+	public static void display(char[] arr) {
+		for (int i = 0; i < arr.length; i++) {
+			System.out.print(arr[i]);
+		}
+		System.out.println();
+	}
+
+	public static void swap(char[] arr, int index1, int index2) {
+		char temp = arr[index1];
+		arr[index1] = arr[index2];
+		arr[index2] = temp;
+	}
+}
+
+
+/* output:
+abc
+acb
+bac
+bca
+cab
+cba
+*/