c++之分支语句和逻辑运算符笔记

cout<<fixed  //用一般的方式输出浮点型，例如Ｃ＋＋程序在控制台显示的时候大一点的数，显示的时候使用了科学计数法，使用该命令即可像一般的方式显示
cout.precision（2） //设置精确度为2，并返回上一次的设置。
cout.setf（iOS_base::showpoint）  //显示浮点数小数点后面的零。

#include<iostream>
#include<fstream>
#include<cstdlib>
const int SIZE = 60;
int main()
{
    using namespace std;
    char filename[SIZE];
    ifstream infile;
    cout << "请输入带读取文件的文件名：";
    cin.getline(filename,SIZE);
    infile.open(filename);
    if (!infile.is_open())
    {
        cout << "打开文件失败！！1" << endl;
        cout << "进程正在结束..." << endl;
        exit(EXIT_FAILURE);
    }
    char data;
    int count = 0;
    infile >> data;
    while (infile.good())
    {
        ++count;
        cout << data;
        infile >> data;
    }
    cout << endl;
    if (infile.eof())
        cout << "文件读取完毕。" << endl;
    else if (infile.fail())
        cout << "数据类型不匹配" << endl;
    else
        cout << "发生未知错误，读取终止。" << endl;
    cout << "文件字符数量为" << count << endl;
    infile.close();
    system("pause");
    return 0;
}

#include<iostream>
#include<string>
using namespace std;
struct patrons
{
    string name;
    double money;
};
int main()
{
    cout << "请输入捐款者总人数： ";
    int number, temp1, temp2;
    number=temp1=temp2=0;
    cin >> number;
    patrons *ps = new patrons[number];
    for (int i = 0; i < number; ++i)
    {
        cout << "请输入第" << i + 1 << "个捐赠者的姓名: ";
        cin >> ps[i].name;
        cout << "请输入捐赠金额： ";
        cin >> ps[i].money;
    }
    cout << "GRAND PATRONS" << endl;
    for (int i = 0;i < number; ++i)
    {
        if (ps[i].money > 10000)
        {
            cout << ps[i].name <<"\t" << ps[i].money << endl;
            ++temp1;
        }
    }
    if (temp1 == 0)
        cout << "none" << endl;
    cout << "PATRONS" << endl;
    for (int i = 0; i < number; ++i)
    {
        if (ps[i].money <= 10000)
        {
            cout << ps[i].name << "\t" << ps[i].money << endl;
            ++temp2;
        }
    }
    if (temp1 == 0)
        cout << "none" << endl;
    delete[]ps;
    system("pause");
    return 0;
}