1. LRU

2.LFU

3. 十字链表，加法，乘法

public class Main {public static void main(String[] args) {CrossLinkedList list = new CrossLinkedList(3, 3);list.insert(0, 0, 1);list.insert(1, 0, 5);list.insert(2, 2, 3);list.display();System.out.println("----------");CrossLinkedList listB = new CrossLinkedList(3, 3);listB.insert(0, 0, 1);// listB.insert(1, 0, 5);listB.insert(2, 2, 3);listB.display();System.out.println("----------");
/*list.add(listB);list.display();System.out.println("----------");*/list.mutiply(listB);list.display();}
}class CrossLinkedList {Node[] rheads, cheads;int rows, cols;CrossLinkedList(int rows, int cols) {this.rows = rows;this.cols = cols;rheads = new Node[rows];cheads = new Node[cols];}public void insert(int row, int col, int value) {Node newNode = new Node(row, col, value);Node currNode = rheads[row];if (null == currNode || currNode.col > newNode.col) {newNode.right = currNode;rheads[row] = newNode;} else {while(currNode.right != null && currNode.right.col < newNode.col) {currNode = currNode.right;}newNode.right = currNode.right;currNode.right = newNode;}currNode = cheads[col];if (null == currNode || currNode.row > newNode.row) {newNode.down = currNode;cheads[col] = newNode;} else {while(currNode.down != null && currNode.down.row < newNode.row) {currNode = currNode.down;}newNode.down = currNode.down;currNode.down = newNode;}}public void display() {for(int i=0; i<rows; i++) {Node currNode = rheads[i];if (null == currNode) {for(int j=0; j<cols; j++) {System.out.printf("0 ");}} else {int j=0;while (j < cols) {if (null == currNode || j < currNode.col) {System.out.printf("0 ");} else {System.out.printf("%d ", currNode.value);currNode = currNode.right;}j++;}}System.out.println();}}public void add(CrossLinkedList N) {Node pa, pb; // 新增两个用于便利两个矩阵的节点Node[] hl = new Node[this.cols];Node pre = null;// 对hl数组初始化，指向每一列的第一个非0元素for(int j=0; j<this.cols; j++) {hl[j] = this.cheads[j];}// 按照行进行遍历for(int i=0; i<this.rows; i++) {pa = rheads[i];pb = N.rheads[i];// pb=null说明矩阵N当前行的非零元素已经遍历完while (pb != null) {Node p = new Node(pb);// 第1种情况: pa为空，或者pa.col > pb.col，此时将 pb 结点插入到矩阵 A 中。if (null == pa || pa.col > pb.col) {// 如果pre=null，说明这行没有非0元素if (pre == null) {rheads[p.row] = p;} else {pre.right = p;}p.right = pa;pre = p;// 在链接好行链表后，链接到对应列的列链表种的相应位置if (this.cheads[p.col] == null || this.cheads[p.col].row > p.row) {p.down = this.cheads[p.col];this.cheads[p.col] = p;} else {p.down = hl[p.col].down;hl[p.col].down = p;}// 更新hl中的数据hl[p.col] = p;} else {// 第2种情况，pa.col < pb.col，只需移动pa的位置，继续判断pa和pb的位置if (pa.col < pb.col) {pre = pa;pa = pa.right;continue;}// 第3，4种情况，当行标和列标都相等的情况下，需要讨论两者相加的值的问题if (pa.col == pb.col) {pa.value += pb.value;if (pa.value == 0) {if (pre == null) {this.rheads[pa.row] = pa.right;} else {pre.right = pa.right;}p = pa;pa = pa.right;if (this.cheads[p.col] == p) {this.cheads[p.col] = hl[p.col] = p.down;} else {hl[p.col].down = p.down;}}}}pb = pb.right;}}}public void mutiply(CrossLinkedList list) {Node prev = null;for(int row=0; row < rows; row++) {Node pa = rheads[row];Node pb = list.rheads[row];while(pa != null) {if (pb == null) {// remove paremove(prev, pa);break;}if (pa.col < pb.col) {remove(prev, pa);pa = pa.right;} else if (pa.col > pb.col) {pb = pb.right;} else {// pb不为null，相乘pa.value *= pb.value;pa = pa.right;pb = pb.right;}prev = pa;}}}public void remove(Node prev, Node node) {if (prev == null) {rheads[node.row] = node.right;return;}prev.right = node.right;}
}class Node {int row, col, value;Node right, down;Node(int row, int col, int value) {this.row = row;this.col = col;this.value = value;}Node(Node node) {this.row = node.row;this.col = node.col;this.value = node.value;}}