add 433

Author: fishercoder1534

Diff for: paginated_contents/algorithms/1st_thousand/README.md

@@ -397,6 +397,7 @@
 | 436 | [Find Right Interval](https://leetcode.com/problems/find-right-interval/)                                                                                                                     | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/firstthousand/_436.java)                                                                  |                                                                               | Medium                           | Binary Search                                                        
 | 435 | [Non-overlapping Intervals](https://leetcode.com/problems/non-overlapping-intervals/)                                                                                                         | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/firstthousand/_435.java)                                                                  |                                                                               | Medium                           | Greedy                                                               
 | 434 | [Number of Segments in a String](https://leetcode.com/problems/number-of-segments-in-a-string/)                                                                                               | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/firstthousand/_434.java)                                                                  |                                                                               | Easy                             |
+| 433 | [Minimum Genetic Mutation](https://leetcode.com/problems/minimum-genetic-mutation/)                                                                                               | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/firstthousand/_433.java)                                                                  |                                                                               | Medium                           | BFS
 | 432 | [All O`one Data Structure](https://leetcode.com/problems/all-oone-data-structure/)                                                                                                            | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/firstthousand/_432.java)                                                                  |                                                                               | Hard                             | Design                                                               
 | 430 | [Flatten a Multilevel Doubly Linked List](https://leetcode.com/problems/flatten-a-multilevel-doubly-linked-list/)                                                                             | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/firstthousand/_430.java)                                                                  |                                                                               | Medium                           | LinkedList, DFS, Doubly-Linked List                                  
 | 429 | [N-ary Tree Level Order Traversal](https://leetcode.com/problems/n-ary-tree-level-order-traversal/)                                                                                           | [Solution](https://github.com/fishercoder1534/Leetcode/blob/master/src/main/java/com/fishercoder/solutions/firstthousand/_429.java)                                                                  |                                                                               | Easy                             | BFS, Tree                                                            

Diff for: src/main/java/com/fishercoder/solutions/firstthousand/_433.java

@@ -0,0 +1,56 @@
+package com.fishercoder.solutions.firstthousand;
+
+import java.util.HashSet;
+import java.util.LinkedList;
+import java.util.Queue;
+import java.util.Set;
+
+public class _433 {
+    public static class Solution1 {
+        /**
+         * My completely original solution, BFS.
+         */
+        public int minMutation(String startGene, String endGene, String[] bank) {
+            boolean found = false;
+            for (String b : bank) {
+                if (b.equals(endGene)) {
+                    found = true;
+                }
+            }
+            if (!found) {
+                return -1;
+            }
+            Queue<String> q = new LinkedList<>();
+            q.offer(startGene);
+            int mutations = 0;
+            Set<String> used = new HashSet<>();
+            used.add(startGene);
+            while (!q.isEmpty()) {
+                int size = q.size();
+                for (int i = 0; i < size; i++) {
+                    String curr = q.poll();
+                    if (curr.equals(endGene)) {
+                        return mutations;
+                    }
+                    for (String candidate : bank) {
+                        if (oneDiff(curr, candidate) && used.add(candidate)) {
+                            q.offer(candidate);
+                        }
+                    }
+                }
+                mutations++;
+            }
+            return -1;
+        }
+
+        private boolean oneDiff(String word1, String word2) {
+            int diffChars = 0;
+            for (int i = 0; i < word1.length(); i++) {
+                if (word1.charAt(i) != word2.charAt(i)) {
+                    diffChars++;
+                }
+            }
+            return diffChars == 1;
+        }
+    }
+}

Diff for: src/test/java/com/fishercoder/firstthousand/_433Test.java

@@ -0,0 +1,34 @@
+package com.fishercoder.firstthousand;
+
+import com.fishercoder.solutions.firstthousand._433;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class _433Test {
+    private static _433.Solution1 solution1;
+
+    @BeforeEach
+    public void setup() {
+        solution1 = new _433.Solution1();
+    }
+
+    @Test
+    public void test1() {
+        assertEquals(-1, solution1.minMutation("AACCGGTT", "AACCGGTA", new String[]{}));
+    }
+
+    @Test
+    public void test2() {
+        assertEquals(-1, solution1.minMutation("AAAAAAAA", "CCCCCCCC",
+                new String[]{"AAAAAAAA", "AAAAAAAC", "AAAAAACC", "AAAAACCC", "AAAACCCC", "AACACCCC", "ACCACCCC", "ACCCCCCC", "CCCCCCCA"}));
+    }
+
+    @Test
+    public void test3() {
+        assertEquals(-1, solution1.minMutation("AAAAAAAT", "CCCCCCCC",
+                new String[]{"AAAAAAAC", "AAAAAAAA", "CCCCCCCC"}));
+    }
+
+}