Java data structure (stack, queue, double-stranded table)

(1) Stack
Package chapterone; public class Stack {// Stack Array long stackarr []; // stack size int maxsize; // The top int top of the stack; // initialize a public stack (INT size) {maxsize = size; stackarr = new long [size]; Top =-1 ;} // public long POP () {return stackarr [top --];} // public void push (long value) {stackarr [++ top] = value;} // determines whether the stack is empty. Public Boolean isempty () {return Top =-1 ;} // determine whether the stack is full public Boolean isfull () {Return Top = maxSize-1;} // get the top element of the stack public long PEEK () {return stackarr [Top];} public static void main (string [] ARGs) {stack = new stack (10); While (! Stack. isfull () {long v = (long) (math. random () * 100); stack. push (V); system. out. print (V + "");} system. out. println (); While (! Stack. isempty () {long topvalue = stack. Pop (); system. Out. Print (topvalue + "") ;}system. Out. println ();}}
(2) queue
Package chapterone; public class queue {// queue array private long queuearr []; // the front-end subscript of the queue private int front; // The tail subscript of the queue private int rear; // queue size private int maxsize; // number of elements in the queue private int nitems; // initialize a queue with the size public Queue (INT size) {queuearr = new long [size]; maxsize = size; front = 0; Rear =-1; nitems = 0 ;}// insert public void insert (long value) {// The queue is full if (Rear = maxSize-1) rear =-1; queuearr [++ Rear] = value; nitems ++;} // Delete public long remove () {long temp = queuearr [Front ++]; If (front = maxsize) front = 0; nitems --; return temp;} // return the first element of the queue public long peakfront () {return queuearr [Front];} // judge whether it is empty public Boolean isempty () {return nitems = 0;} // determine whether it is full public Boolean isfull () {return nitems = maxsize ;} // return the number of elements in the queue. Public int size () {return nitems;} public void print () {( Int I = front; I <front + nitems; I ++) {system. out. print (queuearr [I] + "");} system. out. println ();} public static void main (string [] ARGs) {queue q = new Queue (10); While (! Q. isfull () {long value = (long) (math. Random () * 100); q. insert (value) ;}q. Print (); While (! Q. isempty () {q. remove (); q. print ();} Q. print (); system. out. println (Q. isempty ());}}
(3) priority queue
package ChapterOne;    public class PriorityQueue {        private int nItems;            private long pqArr[];            private int maxSize;            public PriorityQueue(int size){          maxSize = size;          pqArr = new long[size];          nItems = 0;      }            public void insert(long value){          int i;          if(nItems == 0)              pqArr[nItems++] = value;          else{              for(i = nItems-1;i >= 0;i--){                  if(value < pqArr[i]){                      pqArr[i+1] = pqArr[i];                  }                  else                      break;              }              pqArr[i+1] = value;              nItems++;          }      }            public long remove(){          return pqArr[--nItems];      }            public boolean isEmpty(){          return nItems == 0;      }            public boolean isFull(){          return nItems == maxSize;      }            public void print(){          for(int i = 0;i < nItems;i++)              System.out.print(pqArr[i]+" ");          System.out.println();      }            public static void main(String[] args) {          PriorityQueue pq = new PriorityQueue(10);          while(!pq.isFull()){              long value = (long)(Math.random()*100);              pq.insert(value);          }          pq.print();      }  }
(4) double-stranded table
Class Chain {chain pre = NULL, next = NULL; int ID; string name;} class list {private chain header = new chain (); Public chain add (int id, string name) {// Add the node chain current = new chain () at the end of the linked list; // create the Chain List header chain temp = header; while (temp. next! = NULL) // loop to the end of the linked list temp = temp. next; temp. next = current; current. pre = temp; current. id = ID; current. name = Name; Return Current;} public chain remove (int id) {// Delete the node chain temp = header with the specified ID; chain current = NULL; while (temp. next! = NULL) {temp = temp. next; If (temp. id = ID) {current = temp; break;} If (current = NULL) return NULL; current. pre. next = current. next; If (current. next! = NULL) Current. next. pre = current. pre; Return Current;} public chain remove (string name) {// Delete the node chain temp = header with the specified name; chain current = NULL; while (temp. next! = NULL) {temp = temp. next; If (temp. name = Name) {current = temp; break;} If (current = NULL) return NULL; current. pre. next = current. next; If (current. next! = NULL) Current. next. pre = current. pre; Return Current;} public chain remove () {// Delete the last node chain temp = header; while (temp. next. next! = NULL) {temp = temp. next;} temp. next = NULL; return temp;} public void clear () {// Delete All node headers. next = NULL;} public chain insert (int id, string name, int POS) {// insert node chain temp = header at the specified position; chain current = new chain (); int I = 0; for (I = 0; I <= Pos; I ++) {If (temp. next! = NULL) {temp = temp. Next;} else {return NULL;} current. ID = ID; current. Name = Name; If (temp. Next! = NULL) {temp. next. pre = current; current. next = temp. next;} temp. next = current; current. pre = temp; Return Current;} public void print_all () {chain temp = header; system. out. println ("------------------------------------"); While (temp. next! = NULL) {temp = temp. next; system. out. println ("ID:" + temp. ID); system. out. println ("name:" + temp. name);} system. out. println ("------------------------------------") ;}} public class chainlist {public static void main (string [] ARGs) {List A = new list ();. add (1, "Tan Meng Jun 1");. add (2, "Tan Meng Jun 2");. add (3, "Tan mengshu 3");. add (4, "Tan Meng Jun 4");. insert (12, "fat", 2);. print_all ();}}