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Diff for: ‎paginated_contents/algorithms/2nd_thousand/README.md

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| 1469 | [Find All The Lonely Nodes](https://leetcode.com/problems/find-all-the-lonely-nodes/) | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/secondthousand/_1469.java) | | Easy | Tree, DFS |
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| 1466 | [Reorder Routes to Make All Paths Lead to the City Zero](https://leetcode.com/problems/reorder-routes-to-make-all-paths-lead-to-the-city-zero/) | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/secondthousand/_1466.java) | | Medium | Tree, DFS, BFS |
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| 1464 | [Maximum Product of Two Elements in an Array](https://leetcode.com/problems/maximum-product-of-two-elements-in-an-array/) | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/secondthousand/_1464.java) | | Easy | Array |
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| 1462 | [Course Schedule IV](https://leetcode.com/problems/course-schedule-iv/) | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/secondthousand/_1462.java) | | Medium | Topological Sort, DFS, BFS |
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| 1461 | [Check If a String Contains All Binary Codes of Size K](https://leetcode.com/problems/check-if-a-string-contains-all-binary-codes-of-size-k/) | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/secondthousand/_1461.java) | | Medium | String, Bit Manipulation |
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| 1460 | [Make Two Arrays Equal by Reversing Sub-arrays](https://leetcode.com/problems/make-two-arrays-equal-by-reversing-sub-arrays/) | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/secondthousand/_1460.java) | | Easy | Array |
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| 1457 | [Pseudo-Palindromic Paths in a Binary Tree](https://leetcode.com/problems/pseudo-palindromic-paths-in-a-binary-tree/) | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/secondthousand/_1457.java) | | Medium | Bit Manipulation, Tree, DFS |
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| 1143 | [Longest Common Subsequence](https://leetcode.com/problems/longest-common-subsequence/) | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/secondthousand/_1143.java) | | Medium | String, DP
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| 1138 | [Alphabet Board Path](https://leetcode.com/problems/alphabet-board-path/) | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/secondthousand/_1138.java) | [:tv:](https://youtu.be/rk-aB4rEOyU) | Medium | HashTable, String |
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| 1137 | [N-th Tribonacci Number](https://leetcode.com/problems/n-th-tribonacci-number/) | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/secondthousand/_1137.java) | | Easy ||
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| 1136 | [Parallel Courses](https://leetcode.com/problems/parallel-courses/) | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/secondthousand/_1136.java) | | Medium |Topological Sort
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| 1136 | [Parallel Courses](https://leetcode.com/problems/parallel-courses/) | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/secondthousand/_1136.java) | | Medium | Topological Sort
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| 1134 | [Armstrong Number](https://leetcode.com/problems/armstrong-number/) | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/secondthousand/_1134.java) | [:tv:](https://www.youtube.com/watch?v=HTL7fd4HPf4) | Easy ||
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| 1133 | [Largest Unique Number](https://leetcode.com/problems/largest-unique-number/) | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/secondthousand/_1133.java) | [:tv:](https://youtu.be/Fecpt1YZlCs) | Easy ||
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| 1128 | [Number of Equivalent Domino Pairs](https://leetcode.com/problems/number-of-equivalent-domino-pairs/) | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/secondthousand/_1128.java) | [:tv:](https://www.youtube.com/watch?v=7EpEEHAAxyw) | Easy ||
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| 1062 | [Longest Repeating Substring](https://leetcode.com/problems/longest-repeating-substring/) | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/secondthousand/_1062.java) | | Medium | String, Binary Search, DP, Rolling Hash, Suffix Array, Hash Function |
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| 1061 | [Lexicographically Smallest Equivalent String](https://leetcode.com/problems/lexicographically-smallest-equivalent-string/) | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/secondthousand/_1061.java) | [:tv:](https://youtu.be/HvCaMw58_94) | Medium | Union Find
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| 1060 | [Missing Element in Sorted Array](https://leetcode.com/problems/missing-element-in-sorted-array/) | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/secondthousand/_1060.java) | | Medium ||Binary Search
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| 1059 | [All Paths from Source Lead to Destination](https://leetcode.com/problems/all-paths-from-source-lead-to-destination/) | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/secondthousand/_1059.java) | | Medium |DFS
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| 1059 | [All Paths from Source Lead to Destination](https://leetcode.com/problems/all-paths-from-source-lead-to-destination/) | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/secondthousand/_1059.java) | | Medium | DFS
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| 1057 | [Campus Bikes](https://leetcode.com/problems/campus-bikes/) | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/secondthousand/_1057.java) | | Medium ||Greedy, Sort
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| 1056 | [Confusing Number](https://leetcode.com/problems/confusing-number/) | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/secondthousand/_1056.java) | | Easy ||
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| 1055 | [Fixed Point](https://leetcode.com/problems/fixed-point/) | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/secondthousand/_1055.java) | | Easy ||

Diff for: ‎src/main/java/com/fishercoder/solutions/secondthousand/_1462.java

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package com.fishercoder.solutions.secondthousand;
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import java.util.ArrayList;
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import java.util.HashMap;
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import java.util.List;
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import java.util.Map;
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public class _1462 {
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public static class Solution1 {
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/**
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* My completely original solution.
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* DFS + part of topological sort (building the adjacency list)
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*/
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public List<Boolean> checkIfPrerequisite(int numCourses, int[][] prerequisites, int[][] queries) {
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List<Integer>[] graph = new ArrayList[numCourses];
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for (int i = 0; i < numCourses; i++) {
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graph[i] = new ArrayList<>();
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}
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for (int[] pre : prerequisites) {
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graph[pre[0]].add(pre[1]);
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}
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List<Boolean> result = new ArrayList<>();
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//this cache is essential to speed things up, otherwise TLE on LeetCode
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Map<String, Boolean> cache = new HashMap<>();
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for (int[] query : queries) {
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result.add(isPrereq(query[0], query[1], graph, cache));
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}
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return result;
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}
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private Boolean isPrereq(int pre, int target, List<Integer>[] graph, Map<String, Boolean> cache) {
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if (pre == target) {
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cache.put(pre + "-" + target, true);
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return true;
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}
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if (cache.containsKey(pre + "-" + target)) {
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return cache.get(pre + "-" + target);
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}
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for (int v : graph[pre]) {
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if (isPrereq(v, target, graph, cache)) {
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return true;
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}
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}
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cache.put(pre + "-" + target, false);
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return false;
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}
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}
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public static class Solution2 {
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/**TODO: use BFS to solve this problem.*/
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}
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}

Diff for: ‎src/test/java/com/fishercoder/secondthousand/_1462Test.java

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package com.fishercoder.secondthousand;
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import com.fishercoder.common.utils.CommonUtils;
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import com.fishercoder.solutions.secondthousand._1462;
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import org.junit.jupiter.api.BeforeEach;
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import org.junit.jupiter.api.Test;
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import java.util.Arrays;
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import static org.junit.jupiter.api.Assertions.assertEquals;
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public class _1462Test {
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private static _1462.Solution1 solution1;
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@BeforeEach
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public void setup() {
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solution1 = new _1462.Solution1();
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}
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@Test
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public void test1() {
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assertEquals(Arrays.asList(false, true), solution1.checkIfPrerequisite(3,
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CommonUtils.convertLeetCodeRegularRectangleArrayInputIntoJavaArray(
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"[1,0],[2,0]"),
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CommonUtils.convertLeetCodeRegularRectangleArrayInputIntoJavaArray("[0,1],[2,0]")));
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}
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@Test
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public void test2() {
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assertEquals(Arrays.asList(true, true),
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solution1.checkIfPrerequisite(3,
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CommonUtils.convertLeetCodeRegularRectangleArrayInputIntoJavaArray(
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"[1,2],[1,0],[2,0]"),
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CommonUtils.convertLeetCodeRegularRectangleArrayInputIntoJavaArray("[1,0],[1,2]")));
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}
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@Test
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public void test3() {
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assertEquals(Arrays.asList(true, false, true, true, true, true, true, true, false, false, true, true, false, false, true, true, true, true, false, false, true, false, true, false, true, false, true, true, false, true, true, false, false, true, false, false, true, true, true, false),
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solution1.checkIfPrerequisite(7,
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CommonUtils.convertLeetCodeRegularRectangleArrayInputIntoJavaArray(
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"[2,3],[2,1],[2,0],[3,4],[3,6],[5,1],[5,0],[1,4],[1,0],[4,0],[0,6]"),
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CommonUtils.convertLeetCodeRegularRectangleArrayInputIntoJavaArray("[3,0],[6,4],[5,6],[2,6],[2,3],[5,6],[4,0],[2,6],[3,5],[5,3],[1,6],[1,0],[3,5],[6,5],[2,3],[3,0],[3,4],[3,4],[2,5],[0,3],[4,0],[6,4],[5,0],[6,5],[5,6],[6,5],[1,0],[3,4],[1,5],[1,4],[3,6],[0,1],[1,2],[5,1],[5,3],[5,3],[3,4],[5,4],[5,4],[5,3]")));
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}
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}

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