哈弗曼树及其操作
1.哈弗曼樹的節(jié)點(diǎn)聲明
1 package com.neusoft.Tree; 2 3 public class HuffmanNode { 4 public int weight; 5 //加入哈夫曼樹的標(biāo)志,flag=0表示該節(jié)點(diǎn)沒(méi)有加入哈夫曼樹,=1表示加入 6 public int flag; 7 public HuffmanNode parent,lchild,rchild; 8 public HuffmanNode() { 9 this(0); 10 } 11 public HuffmanNode(int weight){ 12 this.weight=weight; 13 flag=0; 14 parent=lchild=rchild=null; 15 } 16 }
點(diǎn)擊可復(fù)制代碼
1 package com.neusoft.Tree; 2 3 public class HuffmanNode { 4 public int weight; 5 //加入哈夫曼樹的標(biāo)志,flag=0表示該節(jié)點(diǎn)沒(méi)有加入哈夫曼樹,=1表示加入 6 public int flag; 7 public HuffmanNode parent,lchild,rchild; 8 public HuffmanNode() { 9 this(0); 10 } 11 public HuffmanNode(int weight){ 12 this.weight=weight; 13 flag=0; 14 parent=lchild=rchild=null; 15 } 16 }點(diǎn)擊+可復(fù)制代碼
2.哈夫曼編碼的構(gòu)建及測(cè)試
1 package com.neusoft.Tree; 2 /** 3 * @author zhao-chj 4 * 哈夫曼樹及其操作 5 */ 6 public class HuffmanTree { 7 8 //求哈夫曼編碼的算法,w存放n個(gè)字符的權(quán)值 9 public int[][] huffmanCoding (int[] w){ 10 int n= w.length;//哈夫曼樹的字符個(gè)數(shù) 11 int m=2*n-1;//哈夫曼樹的節(jié)點(diǎn)個(gè)數(shù) 12 HuffmanNode[] HN =new HuffmanNode[m]; 13 int i=0; 14 for (i = 0; i< n; i++) { 15 HN[i] = new HuffmanNode(w[i]);//構(gòu)造n個(gè)具有權(quán)值的節(jié)點(diǎn) 16 } 17 for (i = n; i< m; i++) { 18 HuffmanNode min1=selectMin(HN,i-1); 19 min1.flag=1;//表示已標(biāo)記 20 HuffmanNode min2=selectMin(HN, i-1); 21 min2.flag=1; 22 //構(gòu)造min1和min2的父節(jié)點(diǎn),并且修改權(quán)值 23 HN[i] =new HuffmanNode(); 24 min1.parent=HN[i]; 25 min2.parent=HN[i]; 26 HN[i].lchild=min1; 27 HN[i].rchild=min2; 28 HN[i].weight=min1.weight+min2.weight; 29 } 30 //從葉子節(jié)點(diǎn)到根逆向求每個(gè)字符的哈夫曼編碼 31 int[][] HuffCode =new int[n][n];//分配n個(gè)字符編碼存儲(chǔ)空間 32 for (int j = 0; j <n; j++) { 33 int start=n-1;//編碼的開(kāi)始位置,初始化為數(shù)組的結(jié)尾 34 for (HuffmanNode c=HN[j],p=c.parent; p!=null; c=p,p=p.parent) { 35 //從葉子結(jié)點(diǎn)到根逆向求解編碼 36 if (p.lchild.equals(c)) {//左孩子編碼為0 37 HuffCode[j][start--] =0; 38 }else { 39 //右孩子編碼為1 40 HuffCode[j][start--]=1; 41 } 42 HuffCode[j][start]=-1;//編碼的開(kāi)始標(biāo)志為-1 43 } 44 } 45 return HuffCode; 46 } 47 /** 48 * 在HN[0...i-1]選擇不再哈夫曼樹中且weight最小的節(jié)點(diǎn) 49 */ 50 private HuffmanNode selectMin(HuffmanNode[] HN, int end) { 51 HuffmanNode min=HN[end]; 52 for (int i = 0; i < end; i++) { 53 HuffmanNode h=HN[i]; 54 if (h.flag==0&&h.weight<min.weight) { 55 //不再哈夫曼樹中且weight最小的節(jié)點(diǎn) 56 min=h; 57 } 58 } 59 return min; 60 } 61 public static void main(String[] args) { 62 int [] w={23,11,5,3,29,14,7,8}; 63 HuffmanTree T =new HuffmanTree();//構(gòu)造哈夫曼樹 64 int [][] HN=T.huffmanCoding(w);//求哈夫曼編碼 65 System.out.println("哈夫曼編碼為:"); 66 for (int i = 0; i < HN.length; i++) { 67 System.out.print(w[i]+" "); 68 for (int j = 0; j < HN[i].length; j++) { 69 if (HN[i][j] ==-1 ) {//數(shù)組結(jié)尾標(biāo)志 70 for (int k = j+1; k < HN[i].length; k++) { 71 System.out.print(HN[i][k]); 72 } 73 break; 74 } 75 } 76 System.out.println(); 77 } 78 } 79 }
點(diǎn)擊可復(fù)制代碼
1 package com.neusoft.Tree; 2 /** 3 * @author zhao-chj 4 * 哈夫曼樹及其操作 5 */ 6 public class HuffmanTree { 7 8 //求哈夫曼編碼的算法,w存放n個(gè)字符的權(quán)值 9 public int[][] huffmanCoding (int[] w){ 10 int n= w.length;//哈夫曼樹的字符個(gè)數(shù) 11 int m=2*n-1;//哈夫曼樹的節(jié)點(diǎn)個(gè)數(shù) 12 HuffmanNode[] HN =new HuffmanNode[m]; 13 int i=0; 14 for (i = 0; i< n; i++) { 15 HN[i] = new HuffmanNode(w[i]);//構(gòu)造n個(gè)具有權(quán)值的節(jié)點(diǎn) 16 } 17 for (i = n; i< m; i++) { 18 HuffmanNode min1=selectMin(HN,i-1); 19 min1.flag=1;//表示已標(biāo)記 20 HuffmanNode min2=selectMin(HN, i-1); 21 min2.flag=1; 22 //構(gòu)造min1和min2的父節(jié)點(diǎn),并且修改權(quán)值 23 HN[i] =new HuffmanNode(); 24 min1.parent=HN[i]; 25 min2.parent=HN[i]; 26 HN[i].lchild=min1; 27 HN[i].rchild=min2; 28 HN[i].weight=min1.weight+min2.weight; 29 } 30 //從葉子節(jié)點(diǎn)到根逆向求每個(gè)字符的哈夫曼編碼 31 int[][] HuffCode =new int[n][n];//分配n個(gè)字符編碼存儲(chǔ)空間 32 for (int j = 0; j <n; j++) { 33 int start=n-1;//編碼的開(kāi)始位置,初始化為數(shù)組的結(jié)尾 34 for (HuffmanNode c=HN[j],p=c.parent; p!=null; c=p,p=p.parent) { 35 //從葉子結(jié)點(diǎn)到根逆向求解編碼 36 if (p.lchild.equals(c)) {//左孩子編碼為0 37 HuffCode[j][start--] =0; 38 }else { 39 //右孩子編碼為1 40 HuffCode[j][start--]=1; 41 } 42 HuffCode[j][start]=-1;//編碼的開(kāi)始標(biāo)志為-1 43 } 44 } 45 return HuffCode; 46 } 47 /** 48 * 在HN[0...i-1]選擇不再哈夫曼樹中且weight最小的節(jié)點(diǎn) 49 */ 50 private HuffmanNode selectMin(HuffmanNode[] HN, int end) { 51 HuffmanNode min=HN[end]; 52 for (int i = 0; i < end; i++) { 53 HuffmanNode h=HN[i]; 54 if (h.flag==0&&h.weight<min.weight) { 55 //不再哈夫曼樹中且weight最小的節(jié)點(diǎn) 56 min=h; 57 } 58 } 59 return min; 60 } 61 public static void main(String[] args) { 62 int [] w={23,11,5,3,29,14,7,8}; 63 HuffmanTree T =new HuffmanTree();//構(gòu)造哈夫曼樹 64 int [][] HN=T.huffmanCoding(w);//求哈夫曼編碼 65 System.out.println("哈夫曼編碼為:"); 66 for (int i = 0; i < HN.length; i++) { 67 System.out.print(w[i]+" "); 68 for (int j = 0; j < HN[i].length; j++) { 69 if (HN[i][j] ==-1 ) {//數(shù)組結(jié)尾標(biāo)志 70 for (int k = j+1; k < HN[i].length; k++) { 71 System.out.print(HN[i][k]); 72 } 73 break; 74 } 75 } 76 System.out.println(); 77 } 78 } 79 }點(diǎn)擊+可復(fù)制上述代碼
3.測(cè)試及運(yùn)行結(jié)果
?
轉(zhuǎn)載于:https://www.cnblogs.com/jackchen-Net/p/6816003.html
總結(jié)
- 上一篇: 狂犬病抗体怎么检测? 是不是要去武汉?一
- 下一篇: 米小圈是谁画的呢?