Merge branch 'master' of github.com:ehlxr/budd

master
ehlxr 2022-06-16 23:20:49 +08:00
commit c1da2bd955
6 changed files with 395 additions and 22 deletions

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@ -0,0 +1,86 @@
/*
* The MIT License (MIT)
*
* Copyright © 2022 xrv <xrv@live.com>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package io.github.ehlxr.algorithm;
import java.util.HashMap;
import java.util.Map;
/**
* @author ehlxr
* @since 2022-04-29 11:07.
*/
public class MinWindow {
public static void main(String[] args) {
System.out.println(minWindow("cabwefgewcwaefgcf", "cae"));
System.out.println(minWindow("bba", "ab"));
System.out.println(minWindow("ADOBECODEBANC", "ABC"));
System.out.println(minWindow("a", "a"));
System.out.println(minWindow("a", "b"));
System.out.println(minWindow("", "a"));
System.out.println(minWindow("", ""));
System.out.println(minWindow("a", "aa"));
System.out.println(minWindow("aa", "a"));
}
public static String minWindow(String s, String t) {
Map<Character, Integer> windows = new HashMap<>();
Map<Character, Integer> needs = new HashMap<>();
for (int i = 0; i < t.length(); i++) {
needs.put(t.charAt(i), needs.getOrDefault(t.charAt(i), 0) + 1);
}
int left = 0, right = 0, valid = 0, start = -1, len = Integer.MAX_VALUE;
while (right < s.length()) {
char r = s.charAt(right);
if (needs.containsKey(r)) {
windows.put(r, windows.getOrDefault(r, 0) + 1);
if (windows.get(r).equals(needs.get(r))) {
valid++;
}
}
right++;
while (valid == needs.size()) {
if (right - left < len) {
len = right - left;
start = left;
}
char l = s.charAt(left);
left++;
if (windows.containsKey(l)) {
if (windows.get(l).equals(needs.get(l))) {
valid--;
}
windows.put(l, windows.get(l) - 1);
}
}
}
return start > -1 ? s.substring(start, start + len) : "";
}
}

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@ -0,0 +1,70 @@
/*
* The MIT License (MIT)
*
* Copyright © 2022 xrv <xrv@live.com>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package io.github.ehlxr.algorithm;
import java.util.ArrayList;
import java.util.List;
/**
*
*
* @author ehlxr
* @since 2022-04-20 16:42.
*/
public class Permutation {
static List<List<Integer>> res = new ArrayList<>();
public static void main(String[] args) {
int[] arr = {1, 2, 3};
for (List<Integer> r : permute(arr)) {
for (int i : r) {
System.out.print(i + " ");
}
System.out.println();
}
}
public static List<List<Integer>> permute(int[] nums) {
List<Integer> track = new ArrayList<>();
backtrack(nums, track);
return res;
}
public static void backtrack(int[] nums, List<Integer> track) {
// 回溯结束条件
if (track.size() == nums.length) {
res.add(new ArrayList<>(track));
return;
}
for (int num : nums) {
if (track.contains(num)) {
continue;
}
track.add(num);
backtrack(nums, track);
track.remove(track.size() - 1);
}
}
}

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@ -39,7 +39,7 @@ public class KnapSack {
public static void main(String[] args) {
System.out.println(knapsack3(new int[]{2, 2, 4, 6, 3}, new int[]{3, 4, 8, 9, 6}, 5, 9));
System.out.println(knapsack(new int[]{2, 2, 4, 6, 3}, new int[]{3, 4, 8, 9, 6}, 5, 9));
// System.out.println(knapsack(new int[]{2, 2, 4, 6, 3}, new int[]{3, 4, 8, 9, 6}, 5, 9));
}
/**
@ -51,17 +51,17 @@ public class KnapSack {
* @param w
* @return
*/
public static int knapsack(int[] weight, int[] value, int n, int w) {
int[][] dp = new int[][];
}
// public static int knapsack(int[] weight, int[] value, int n, int w) {
// int[][] dp = new int[][];
// }
/**
*
*
* @param weight
* @param value
* @param n
* @param w
* @param n
* @param w
* @return
*/
public static int knapsack3(int[] weight, int[] value, int n, int w) {

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@ -0,0 +1,95 @@
/*
* The MIT License (MIT)
*
* Copyright © 2022 xrv <xrv@live.com>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package io.github.ehlxr.algorithm.linkedlist;
/**
* @author ehlxr
* @since 2022-05-01 14:18.
*/
public class FindKthFromEnd {
public static void main(String[] args) {
ListNode head = new ListNode(1);
head.next = new ListNode(2);
head.next.next = new ListNode(3);
head.next.next.next = new ListNode(4);
head.next.next.next.next = new ListNode(5);
head.next.next.next.next.next = new ListNode(6);
System.out.println(head);
System.out.println(findKthFromEnd(head, 1));
System.out.println(findKthFromEnd2(head, 1));
}
public static ListNode findKthFromEnd(ListNode head, int k) {
int n = 0;
ListNode node = head;
ListNode p = null;
while (node != null) {
if (p != null) {
p = p.next;
}
n++;
if (n == k) {
p = head;
}
node = node.next;
}
return p;
}
public static ListNode findKthFromEnd2(ListNode head, int k) {
ListNode p = head;
ListNode q = head;
for (int i = 0; i < k; i++) {
q = q.next;
}
while (q != null) {
p = p.next;
q = q.next;
}
return p;
}
static class ListNode {
int val;
ListNode next;
ListNode(int x) {
val = x;
}
@Override
public String toString() {
return "ListNode{" +
"val=" + val +
", next=" + next +
'}';
}
}
}

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@ -0,0 +1,92 @@
/*
* The MIT License (MIT)
*
* Copyright © 2022 xrv <xrv@live.com>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package io.github.ehlxr.algorithm.linkedlist;
/**
* @author ehlxr
* @since 2022-05-03 14:26.
*/
public class ReverseKGroup {
public static void main(String[] args) {
ListNode head = new ListNode(1);
head.next = new ListNode(2);
head.next.next = new ListNode(3);
head.next.next.next = new ListNode(4);
head.next.next.next.next = new ListNode(5);
System.out.println(head);
System.out.println(reverseKGroup(head, 2));
}
public static ListNode reverseKGroup(ListNode head, int k) {
ListNode p = head;
for (int i = 0; i < k; i++) {
if (p == null) {
return head;
}
p = p.next;
}
ListNode r = reverseN(head, p);
head.next = reverseKGroup(p, k);
return r;
}
public static ListNode reverseN(ListNode head, ListNode n) {
ListNode cur = head, pre = null;
while (cur != n) {
ListNode next = cur.next;
cur.next = pre;
pre = cur;
cur = next;
}
return pre;
}
public static class ListNode {
int val;
ListNode next;
ListNode() {
}
ListNode(int val) {
this.val = val;
}
ListNode(int val, ListNode next) {
this.val = val;
this.next = next;
}
@Override
public String toString() {
return "ListNode{" +
"val=" + val +
", next=" + next +
'}';
}
}
}

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@ -36,17 +36,53 @@ public class ReverseLinkedList {
Node node4 = new Node(4, node5);
Node node3 = new Node(3, node4);
Node node2 = new Node(2, node3);
Node node1 = new Node(1, node2);
Node node0 = new Node(0, node1);
Node root = new Node(null, node0);
Node head = new Node(1, node2);
Node reverse = reverse(root);
// root.print();
// Node reverse = reverse(root);
// reverse.print();
reverse.print();
// System.out.println(reverseToN(head, node3));
// System.out.println(reverseToN(head, 2));
System.out.println(reverseFm2N(head, 2, 4));
}
public static Node reverseToN(Node root, Node n) {
Node pre = null, cur = root, tmp = root;
while (cur != n) {
tmp = cur.next;
cur.next = pre;
pre = cur;
cur = tmp;
}
return pre;
}
static Node next = null;
public static Node reverseToN(Node root, int n) {
if (n == 1) {
next = root.next;
return root;
}
Node h = reverseToN(root.next, n - 1);
root.next.next = root;
root.next = next;
return h;
}
public static Node reverseFm2N(Node root, int m, int n) {
if (m == 1) {
return reverseToN(root, n);
}
root.next = reverseFm2N(root.next, m - 1, n - 1);
return root;
}
public static Node reverse(Node root) {
Node pre = null;
@ -73,17 +109,11 @@ class Node {
this.value = value;
}
public void print() {
System.out.println(this);
Node tmp = this.next;
while (tmp != null) {
System.out.println(tmp);
tmp = tmp.next;
}
}
@Override
public String toString() {
return "Node[value=" + this.value + "]";
return "Node{" +
"value=" + value +
", next=" + next +
'}';
}
}