Java Utililty Methods Integer Array Permutation

List of utility methods to do Integer Array Permutation

HOME
Java
I
Integer Array Permutation

Description

The list of methods to do Integer Array Permutation are organized into topic(s).

Method

int nextPermutation(int v)
Permutates the bits with value 1 in bitstring v, return next permutation

if (v == 0)
 return 0;
else {
 int t = (v | (v - 1)) + 1;
 return t | ((((t & -t) / (v & -v)) >> 1) - 1);

int[] nextPermutation(int[] arr)
next Permutation

int[] a = (int[]) arr.clone();
int n = a.length - 1;
int j = n - 1;
while (a[j] > a[j + 1]) {
 if (j == 0) {
 int[] error = new int[] { 0 };
 return error;
 j--;
int k = n;
while (a[j] > a[k]) {
 k--;
int tmp = a[j];
a[j] = a[k];
a[k] = tmp;
int r = n;
int s = j + 1;
while (r > s) {
 tmp = a[r];
 a[r] = a[s];
 a[s] = tmp;
 r--;
 s++;
return a;

boolean nextPermutation(int[] is)
next Permutation

int n = is.length;
for (int i = n - 1; i > 0; i--) {
 if (is[i - 1] < is[i]) {
 int j = n;
 while (is[i - 1] >= is[--j])
 ;
 swap(is, i - 1, j);
 rev(is, i, n);
...

int[] nextPermutation(int[] next)
next Permutation

int gt = -1;
for (int idx = 0; idx < next.length - 1; idx++) {
 if (next[idx] < next[idx + 1]) {
 gt = idx;
if (gt == -1) {
 return null;
...

void nextPermutation(int[] nums)
next Permutation

int n = nums.length;
int i;
for (i = n - 2; i >= 0; --i) {
 if (nums[i] < nums[i + 1]) {
 break;
if (i < 0) {
...