实验7

Posted 2020-11-19 yywzs

 1 #include<iostream>
 2 #include<string>
 3 #include<fstream>
 4 #include<vector>
 5 #include<stdlib.h>
 6 #include<time.h>
 7 using namespace std;
 8 struct student{
 9         int id;
10         long long stu_num;
11         string name;
12         string sub;
13 };
14 int main(){
15     int i,n;
16     srand(time(NULL));
17     ifstream readfile("list.txt");
18     student stu[83];
19     for(i=0;i<83;i++){
20         readfile>>stu[i].id>>stu[i].stu_num>>stu[i].name>>stu[i].sub;
21     } 
22     readfile.close();
23     ofstream writefile("roll.txt",ios_base::app);
24     for(i=0;i<5;i++){
25         n=rand()%82;
26         writefile<<stu[n].id<<" "<<stu[n].stu_num<<" "<<stu[n].name<<" "<<stu[n].sub<<endl;
27         cout<<stu[n].id<<" "<<stu[n].stu_num<<" "<<stu[n].name<<" "<<stu[n].sub<<endl;
28     }
29     writefile.close();
30 } 

 

 

 

 1 #include<fstream>
 2 #include<iostream>
 3 #include<string>
 4 using namespace std;
 5 int main(){
 6     char s[50]={"test1.txt"};
 7     string f;
 8     ofstream file(s,ios::app);
 9     file.write("已经成功写入!",sizeof("已经成功写入!"));
10     file.close();
11     ifstream file2(s);
12     getline(file2,f);
13     cout<<f; 
14     file2.close();
15     return 0;
16     
17 } 

 

 1 #include<iostream>
 2 #include<fstream>
 3 #include<string>
 4 #include<vector>
 5 using namespace std;
 6 int main(){
 7     int n=0,i,sum=0;
 8     string s,ss;
 9     cin>>s;
10     vector <string> str;
11     ifstream readf(s.c_str());
12     while(getline(readf,ss)){
13         str.push_back(ss);
14         n++;
15     }
16     for(i=0;i<n;i++){
17         sum+=str[i].size();
18     }
19     cout<<"字数:"<<sum<<endl<<"行数:"<<n<<endl;
20 }