blob: cccb25c4b776c874cda86f15912c77cfbfc1cc50 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
|
class Node {
int value;
Node left, right;
Node(int item) {
value = item;
left = right = null;
}
}
public class Main {
Node root;
boolean isBST() {
return isBSTUtil(root, Integer.MIN_VALUE, Integer.MAX_VALUE);
}
boolean isBSTUtil(Node node, int min, int max) {
if (node == null) {
return true;
}
if (node.value < min || node.value > max) {
return false;
}
return (isBSTUtil(node.left, min, node.value - 1) &&
isBSTUtil(node.right, node.value + 1, max));
}
public static void main(String args[]) {
Main tree = new Main();
tree.root = new Node(8);
tree.root.left = new Node(5);
tree.root.right = new Node(9);
tree.root.left.left = new Node(4);
tree.root.left.right = new Node(6);
if (tree.isBST()) {
System.out.println(1);
} else {
System.out.println(0);
}
}
}
|
