leetcode:path sum

realDuYuanChao · realDuYuanChao · commit 419ff7e643e7 · 2020-11-23T14:03:38.000+08:00
diff --git a/src/main/java/com/examplehub/leetcode/easy/PathSum.java b/src/main/java/com/examplehub/leetcode/easy/PathSum.java
@@ -0,0 +1,15 @@
+package com.examplehub.leetcode.easy;
+
+import com.examplehub.datastructures.binarytree.Node;
+
+public class PathSum {
+  public static boolean solution1(Node<Integer> node, int sum) {
+    if (node == null) {
+      return false;
+    }
+    if (node.value == sum && node.left == null && node.right == null) {
+      return true;
+    }
+    return solution1(node.left, sum - node.value) || solution1(node.right, sum - node.value);
+  }
+}
diff --git a/src/test/java/com/examplehub/leetcode/easy/PathSumTest.java b/src/test/java/com/examplehub/leetcode/easy/PathSumTest.java
@@ -0,0 +1,26 @@
+package com.examplehub.leetcode.easy;
+
+import com.examplehub.datastructures.binarytree.Node;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+class PathSumTest {
+  @Test
+  void testSolution1() {
+    Node<Integer> root = new Node<>(5);
+    root.left = new Node<>(4);
+    root.right = new Node<>(8);
+    root.left.left = new Node<>(11);
+    root.right.left = new Node<>(13);
+    root.right.right = new Node<>(4);
+    root.left.left.left = new Node<>(7);
+    root.left.left.right = new Node<>(2);
+    root.right.right.right = new Node<>(1);
+
+    assertTrue(PathSum.solution1(root, 22));
+    assertTrue(PathSum.solution1(root, 26));
+    assertFalse(PathSum.solution1(root, 100));
+  }
+}
