第7次C++实验

#include<iostream>
using namespace std;
int main()
{
    ios_base::fmtflags original_flags=cout.flags();//切换输出模式类的声明
    cout<<812<<"|";
    cout.setf(ios_base::left,ios_base::adjustfield);//确定输出内容的对齐方向为左对齐
    cout.width(10);//确定输出内容宽度为10
    cout<<813<<815<<"\n";
    cout.unsetf(ios_base::adjustfield);//清除对齐方式
    cout.precision(2);//确定输出数值精确度为小数点后两位
    cout.setf(ios_base::uppercase|ios_base::scientific);//转换到科学计数法模式
    cout<<831.0;
    cout.flags(original_flags);//转换回标准输出模式；
    return 0;
}

#include<fstream>
using namespace std;
int main()
{
    ofstream file1("test1.txt");
    file1<<"The file has been written successfully";
    file1.close();
    return 0;
}

#include<fstream>
#include<iostream>
using namespace std;
int main()
{
    char ch;
    ifstream file2("test1.txt");
    while(file2.get(ch))
    {
        cout<<ch;
    }
    file2.close();
    return 0;
}

#include<iostream>
#include<cstdlib>
#include<string>
#include<fstream>
using namespace std;
struct student
{
    string num;
    string snum;
    string name;
    string cla;
}a[200];
using namespace std;
int main()
{
    int i,j,n=0;
    ifstream fin("list.txt");
    while(fin>>a[n].num>>a[n].snum>>a[n].name>>a[n].cla)
    {
        n++;
    }
    fin.close();
    ofstream fout("roll.txt");
    for(i=0;i<5;i++)
    {
        j=rand()%n+1;
        cout<<a[j].num<<" "<<a[j].snum<<" "<<a[j].name<<" "<<a[j].cla<<endl;
        fout<<a[j].num<<" "<<a[j].snum<<" "<<a[j].name<<" "<<a[j].cla<<endl;
    }
    fout.close();
    return 0;
}

#include<iostream>
#include<fstream>
#include<string>
using namespace std;
int main()
{
    ifstream in("article.txt");
    int line=0,word=0,num=0;
    string s;
    int i,m;
    while(getline(in,s))
    {
        line++;
        m=s.size();
        num=num+m;
        for(i=0;i<m;i++)
        {
            if((s[i]>=‘A‘&&s[i]<=‘Z‘)||(s[i]>=‘a‘&&s[i]<=‘z‘))
            {
                if((s[i+1]<=‘A‘||s[i+1]>=‘Z‘)&&(s[i+1]<=‘a‘||s[i+1]>=‘z‘))
                {
                    word=word+1;
                }
            }
        }
    }
    cout<<"The article has "<<line<<" lines, "<<word<<" words, "<<num<<" letters.";
    return 0;
}