38 lines
828 B
Java
38 lines
828 B
Java
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public class Queue<T>
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{
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private Node<T> first;
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private Node<T> last;
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public Queue(){
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this.first = null;
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this.last = null;
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}
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public boolean isEmpty(){
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return this.first == null;
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}
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public void enqueue(T val){
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Node<T> added = new Node<T>(val);
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Node<T> current = this.first;
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if (this.first == null){
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this.first = added;
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this.last = added;
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}
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else{
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this.last.next = added;
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this.last = added;
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}
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}
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public T dequeue (){
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if (this.first == null) return null;
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T ret = this.first.wert;
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this.first = this.first.next;
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return ret;
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}
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public T front (){
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if (this.first == null) return null;
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return this.first.wert;
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}
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}
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