Question

我正在编写一个程序，该程序应打印数据文件中每个字母的使用情况。数据文件如下所示：“您好，世界一切都很棒。您好，世界一切都很棒。您好，我的世界也很棒。”如果运行该程序，它将从A-z（65-122）打印出ASCI表中的每个字符，并打印出它的出现。我的问题是，有没有办法打印出数据文件中使用的唯一字符及其出现的内容？这是我的代码：

#include "stdafx.h"
#include<iostream>
#include <fstream>
#include <string>

using namespace std;
const int SIZE = 128;

void storeFunction(int store[]);

void storeFunction(int store[])
{
    ifstream in; //declares input file
    in.open("mytext.dat"); //reading file
    char Check; //declaration to read each character in the file

    if (in.fail())
    {
        cout << "Text did not open correctly." << endl;
    }
    else
    {
        while (!in.eof()) {
            in >> Check; //saving each single character in Check

            store[Check]++; //this loop will find each letter, with the ASCI table, and store it in Check.

        }
        for (int i = 'A'; i < 'z'; i++)
        {
            cout << "Character: "<< char(i) << " Frequency: " << store[i] << endl;
        }
    }
    in.close();
}
int main()
{
    int store[SIZE] = { 0 }; //setting the initializer list to 0.

    storeFunction(store); //call the function

    return 0;
}

谢谢。

Answer 1

#include<iostream>
#include <fstream>
#include <string>
#include <unordered_map>

using namespace std;

void printCharOccurance();
void printCharOccurance()
{
    ifstream in; //declares input file
    in.open("mytext.dat"); //reading file
    char readChar;

    if (in.fail())
    {
        cout << "Failed to open the file" << endl;
    }
    else
    {
        unordered_map<char,int> storeCharacterOccurance;
        while (!in.eof()) {
            in >> readChar; //saving each single character in readChar
            if(!(((readChar >='a') && (readChar <='z')) || ((readChar >='A') && (readChar <='Z'))))
                        continue;       
            storeCharacterOccurance[readChar]++; //this loop will iterate over each character in file if character is a-z or A-Z

        }
        for (auto& x: mymap) {
            cout << "Character: "<< x.first << " Frequency: " << x.second << endl;
        }
    }
    in.close();
}
int main()
{
    printCharOccurance(); //call the function

    return 0;
}

是否可以从仅使用C ++文件中字符的数据文件中打印字符的频率？

1 个答案: