统计短文中各字符的频度

//主要算法，二叉排序树的查找

//以出现的各字符构成一棵二叉排序树，针对每一个字符在二叉树中查找，如果找到了就增加计数，否则就插入#include<iostream>#include<string>#include<fstream>using namespace std;typedef char KeyType;struct BstNode {    KeyType data;    int num;    BstNode *lch,*rch;};class BstTree{private:    BstNode *root;    BstNode* insert(BstNode *t,BstNode *s);    void inorder(ofstream& outfile,BstNode *p);    void deletenode(BstNode *p);public:    BstTree(){root=NULL;}    ~BstTree(){delete(root);root=NULL;}    void read_creat(ifstream& infile);    void print_inorder(ofstream& outfile)        {inorder(outfile,root);}};BstNode* BstTree::insert(BstNode *t,BstNode *s){    if(t==NULL){t=s;t->num=1;}    else if(t->data==s->data){delete(s);s=NULL;t->num++;}    else     {        if(t->data>s->data)t->lch=insert(t->lch,s);        else t->rch=insert(t->rch,s);    }    return t;}void BstTree::read_creat(ifstream& infile){    char ch;     infile.get(ch);    while(infile)    {        BstNode *s;s=new BstNode;s->data=ch;s->num=1;s->lch=s->rch=NULL;        root=insert(root,s);        infile.get(ch);    }}void BstTree::deletenode(BstNode *p){    if(p!=NULL)    {        deletenode(p->lch);deletenode(p->rch);        delete p;    }}void BstTree::inorder(ofstream& outfile,BstNode *p){    if(p!=NULL)    {        inorder(outfile,p->lch);        outfile<<p->data<<"    "<<p->num<<endl;        inorder(outfile,p->rch);    }}void main(){    ifstream infile;ofstream outfile;infile.open("E:\c++.txt");    if(!infile){cout<<"open file failure!n";return;}        outfile.open("E:\b++.txt");    BstTree tree;    tree.read_creat(infile);    tree.print_inorder(outfile);    infile.close();outfile.close();}

读取文本中的字符并计算出各字母出现的次数

//读取文本中的字符并计算出各字母出现的次数#include<iostream>#include<fstream>#include<cctype>using namespace std;void initialize(int& lc,int list[]);void copyText(ifstream& intext,ofstream& outtext,char& ch,int list[]);void characterCount(char ch,int list[]);void writeTotal(ofstream& outtext,int lc,int list[]);int main(){    int lineCount;    int listLetter[26];    char ch;    ifstream infile;    ofstream outfile;    infile.open("C:\c++.txt");    if(!infile)    {        cout<<"Cannot open input file."<<endl;        return 1;    }    outfile.open("C:\b++.txt");    initialize(lineCount,listLetter);    infile.get(ch);    while(infile)    {        copyText(infile,outfile,ch,listLetter);        lineCount++;            infile.get(ch);    }    writeTotal(outfile,lineCount,listLetter);    infile.close();    outfile.close();        return 0;}void initialize(int& lc,int list[]){    int j;    lc=0;    for(j=0;j<26;j++)        list[j]=0;}void copyText(ifstream& intext,ofstream& outtext,char& ch,int list[]){    while(ch!='n')    {        outtext<<ch;                      //输出原文本的信息        characterCount(ch,list);        intext.get(ch);    }    outtext<<ch;                         //原文本断行时新文本也断行}void characterCount(char ch,int list[]){    int index;    ch=toupper(ch);    index=static_cast<int>(ch)-65;    if(0<=index && index<26)        list[index]++;}void writeTotal(ofstream& outtext,int lc,int list[]){    int index;    outtext<<endl<<endl;    outtext<<"The number of lines="<<lc<<endl;    for(index=0;index<26;index++)        outtext<<static_cast<char>(index+65)<<" count = "<<list[index]<<endl;}/*sampleC:\c++.txt:fwwwewefqtgqtggrqgrgqeerghhwhwewhtfwqfqgqrewgqegqrgergqegrqcwoifuqiwofjeiopjwesvjxvzvmxnbdmeioejgeorigjqioadf;klsajfpoiqfew;fjwf54651844fwgqrwegergqwereaC:\b++.txt:fwwwewefqtgqtggrqgrgqeerghhwhwewhtfwqfqgqrewgqegqrgergqegrqcwoifuqiwofjeiopjwesvjxvzvmxnbdmeioejgeorigjqioadf;klsajfpoiqfew;fjwf54651844fwgqrwegergqwereaThe number of lines=6A count = 3B count = 1C count = 1D count = 2E count = 19F count = 12G count = 17H count = 4I count = 7J count = 7K count = 1L count = 1M count = 2N count = 1O count = 7P count = 2Q count = 16R count = 11S count = 2T count = 3U count = 1V count = 3W count = 17X count = 2Y count = 0Z count = 1*/

原文链接: https://www.cnblogs.com/mjc467621163/archive/2011/08/23/2151014.html

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