public class _24_Test {
public static void main(String[] args) {
int[] array={1,5,2,4,3};
_24_Test test=new _24_Test();
System.out.println(test.verityBST(array));
}
public boolean verityBST(int [] sequence) {
if (sequence.length == 0) {
return false;
}
return IsBST(sequence,0,sequence.length - 1);
}
private boolean IsBST(int[] sequence, int start, int end) {
if (end <= start) {
return true;
}
int i = start;
for (; i < end; i++) {
if (sequence[i] > sequence[end]) {
break;
}
}
for (int j = i; j < end; j++) {
if (sequence[j] < sequence[end]) {
return false;
}
}
return IsBST(sequence, start, i - 1) && IsBST(sequence, i, end - 1);
}
}