This is my node and driver class. I need to find the smallest value on the left side of the tree.
import java.util.ArrayList;
import java.util.List;
public class NTreeNode<T> {
public T value;
public List<NTreeNode<T>> children;
public NTreeNode(T val) {
value = val;
children = new ArrayList<NTreeNode<T>>();
}
public String toString() {
return value + "@" + children;
}
public String toString(String indent) {
String result = indent + value + "\n";
for (NTreeNode<T> child : children) {
result += child.toString(indent + " ");
}
return result;
}
/** Helper method to make it easier to construct trees.
* The first data value is always the root value.
* The path values must give the index of each node in the path
* to the parent node of the next value you wish to insert.
* Parent nodes MUST appear in the list before their children.
* @param paths The path to the parent of the next value.
* @param data The value to insert into the tree.vv
* @return NTreeNode<T> The root of the constructed tree.
*/
public static <T extends Comparable<? super T>>
NTreeNode<T> buildTree(List<String> paths, List<T> data) {
// Sanity check inputs.
if ((paths == null) || (data == null) ||
(paths.size() != data.size()) || (paths.size() < 1)) {
return null;
}
// Root node.
NTreeNode<T> root = new NTreeNode<T>(data.get(0));
// Remaining values.
for (int pos = 1; pos < paths.size(); pos++) {
NTreeNode<T> current = root;
String path = paths.get(pos);
// Find the parent node of the next value to be inserted.
for (int step = 0; step < path.length(); step++) {
current = current.children.get(Integer.parseInt(""+path.charAt(step)));
}
// Add the new node to the tree at the correct location.
current.children.add(new NTreeNode<T>(data.get(pos)));
}
return root;
}
public static void main(String[] args) {
ArrayList<String> paths = new ArrayList<String>();
ArrayList<String> data = new ArrayList<String>();
paths.add(""); data.add("root");
paths.add(""); data.add("A");
paths.add(""); data.add("B");
paths.add(""); data.add("C");
paths.add("0"); data.add("A-A");
paths.add("1"); data.add("B-A");
paths.add("1"); data.add("B-B");
paths.add("1"); data.add("B-C");
paths.add("2"); data.add("C-A");
paths.add("00"); data.add("A-A-A");
paths.add("10"); data.add("B-A-A");
paths.add("11"); data.add("B-B-A");
paths.add("12"); data.add("B-C-A");
paths.add("100"); data.add("B-A-A-A");
System.out.println(buildTree(paths, data).toString(""));
}
}what I've done so far is this, but it doesn't work.
public class TreeMinimum<T extends Comparable<? super T>> {
public T findMin (NTreeNode<T> root) {
int min = Integer.MAX_VALUE;
if (root == null)
return null;
else if (root.children == null)
return root.value;
for (int i=0; i<root.children.size()-1;i++) {
while (root.children != null) {
root = root.children.get(i);
if (root.value < min)
min = root.value;
}
}
return min;
}
}