Given an array, rotate the array to the right by k steps, where k is non-negative.
Example 1:
Input: [1,2,3,4,5,6,7] and k = 3
Output: [5,6,7,1,2,3,4]
Explanation:
rotate 1 steps to the right: [7,1,2,3,4,5,6]
rotate 2 steps to the right: [6,7,1,2,3,4,5]
rotate 3 steps to the right: [5,6,7,1,2,3,4]
Example 2:
Input: [-1,-100,3,99] and k = 2
Output: [3,99,-1,-100]
Explanation:
rotate 1 steps to the right: [99,-1,-100,3]
rotate 2 steps to the right: [3,99,-1,-100]
import java.util.Arrays;
public class App {
public static void main(String[] args) {
int[] input = {1, 2, 3, 4, 5, 6, 7};
rotate(input, 3);
System.out.println(Arrays.toString(input));
}
public static void rotate(int[] nums, int k) {
for(int i = 1; i<= k; i++) {
rotateArrayByOne(nums);
}
}
public static void rotateArrayByOne(int[] nums) {
int last = nums[nums.length-1];
for(int i = nums.length-2; i >= 0; i--) {
nums[i+1] = nums[i];
}
nums[0] = last;
}
}Above implementation have Runtime complexity of O(kn) and space complexity of O(1)
Runtime Complexity = O(kn)
Space Complexity = O(1)
import java.util.Arrays;
public class App {
public static void main(String[] args) {
int[] input = { 1, 2};
rotate(input, 3);
System.out.println(Arrays.toString(input));
}
public static void rotate(int[] nums, int k) {
int[] temp = new int[nums.length];
for(int i = 0; i < nums.length; i++) {
temp[(i+k) % nums.length] = nums[i];
}
for(int i = 0; i < temp.length; i++) {
nums[i] = temp[i];
}
}
}Above implementation have Runtime complexity of O(n) and space complexity of O(n)
Runtime Complexity = O(n)
Space Complexity = O(n)
import java.util.Arrays;
public class App {
public static void main(String[] args) {
int[] input = {1, 2};
rotate(input, 3);
System.out.println(Arrays.toString(input));
}
public static void rotate(int[] nums, int k) {
k %= nums.length;
int length = nums.length;
int[] temp = new int[k];
for(int i = 0; i < k; i++) {
temp[i] = nums[length - k + i];
}
for(int i = length - k - 1; i >= 0; i--) {
nums[i + k] = nums[i];
}
for(int i = 0; i < k; i++) {
nums[i] = temp[i];
}
}
}Above implementation have Runtime complexity of O(n) and space complexity of O(k)
Runtime Complexity = O(n)
Space Complexity = O(k)
import java.util.Arrays;
public class App {
public static void main(String[] args) {
int[] input = { 1, 2, 3, 4, 5, 6, 7 };
rotate(input, 3);
System.out.println(Arrays.toString(input));
}
public static void rotate(int[] nums, int k) {
k = k % nums.length;
reverse(nums, nums.length - k, nums.length - 1);
reverse(nums, 0, nums.length - k - 1);
reverse(nums, 0, nums.length - 1);
}
public static void reverse(int[] nums, int start, int end) {
while (start < end) {
int temp = nums[start];
nums[start++] = nums[end];
nums[end--] = temp;
}
}
}Above implementation have Runtime complexity of O(n) and space complexity of O(1)
Runtime Complexity = O(n)
Space Complexity = O(1)
k = k % nums.length;