查找字符串中元音、辅音、数字和空格数的 C++ 程序

在此示例中，我们将学习查找 C++ 字符串中存在的元音、辅音、数字和空格的数量。

要理解此示例，您应该具备以下 C++ 编程主题的知识：

示例 1：来自 C 风格的字符串

这个程序从用户那里获取一个 C 风格的字符串并计算元音、辅音、数字和空格的数量。

#include <iostream>
using namespace std;

int main()
{
    char line[150];
    int vowels, consonants, digits, spaces;

    vowels =  consonants = digits = spaces = 0;

    cout << "Enter a line of string: ";
    cin.getline(line, 150);
    for(int i = 0; line[i]!='\0'; ++i)
    {
        if(line[i]=='a' || line[i]=='e' || line[i]=='i' ||
           line[i]=='o' || line[i]=='u' || line[i]=='A' ||
           line[i]=='E' || line[i]=='I' || line[i]=='O' ||
           line[i]=='U')
        {
            ++vowels;
        }
        else if((line[i]>='a'&& line[i]<='z') || (line[i]>='A'&& line[i]<='Z'))
        {
            ++consonants;
        }
        else if(line[i]>='0' && line[i]<='9')
        {
            ++digits;
        }
        else if (line[i]==' ')
        {
            ++spaces;
        }
    }

    cout << "Vowels: " << vowels << endl;
    cout << "Consonants: " << consonants << endl;
    cout << "Digits: " << digits << endl;
    cout << "White spaces: " << spaces << endl;

    return 0;
}

输出

Enter a line of string: This is 1 hell of a book.
Vowels: 7
Consonants: 10
Digits: 1
White spaces: 6

示例 2：来自字符串对象

该程序从用户那里获取一个字符串对象并计算元音、辅音、数字和空格的数量。

#include <iostream>
using namespace std;

int main()
{
    string line;
    int vowels, consonants, digits, spaces;

    vowels =  consonants = digits = spaces = 0;

    cout << "Enter a line of string: ";
    getline(cin, line);

    for(int i = 0; i < line.length(); ++i)
    {
        if(line[i]=='a' || line[i]=='e' || line[i]=='i' ||
           line[i]=='o' || line[i]=='u' || line[i]=='A' ||
           line[i]=='E' || line[i]=='I' || line[i]=='O' ||
           line[i]=='U')
        {
            ++vowels;
        }
        else if((line[i]>='a'&& line[i]<='z') || (line[i]>='A'&& line[i]<='Z'))
        {
            ++consonants;
        }
        else if(line[i]>='0' && line[i]<='9')
        {
            ++digits;
        }
        else if (line[i]==' ')
        {
            ++spaces;
        }
    }

    cout << "Vowels: " << vowels << endl;
    cout << "Consonants: " << consonants << endl;
    cout << "Digits: " << digits << endl;
    cout << "White spaces: " << spaces << endl;

    return 0;
}

输出

Enter a line of string: I have 2 C++ programming books.
Vowels: 8
Consonants: 14
Digits: 1
White spaces: 5