66 lines
1.2 KiB
Java
66 lines
1.2 KiB
Java
public class Queue<T>
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{
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private Node<T> first;
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public Queue() {
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first = null;
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}
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public boolean isEmpty() {
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if (first == null) return true;
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return false;
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}
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public T front(int n) {
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Node<T> current = first;
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for (int i = 0; i < n; i++) {
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if (current == null) return null;
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current = current.next;
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}
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if (current == null) return null;
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return current.wert;
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}
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public void enqueue(T val) {
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Node<T> neu = new Node<T>();
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neu.wert = val;
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if (first == null) {
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first = neu;
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} else {
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Node<T> current = first;
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while (current.next != null) {
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current = current.next;
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}
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current.next = neu;
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}
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}
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public T dequeue() {
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T tmp = first.wert;
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first = first.next;
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return tmp;
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}
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public String toString(){
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String result = "";
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Node<T> current = first;
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while (current != null) {
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result += current.wert + ", ";
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current = current.next;
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}
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return result;
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}
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}
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