cplus 实验二

//2-28-(1)
#include <iostream>
using namespace std;
int main()
{
 char x;
 cout<<"Menu: A(dd) D(elete) S(ort) Q(uit),Select one:"<<endl;
 cin>>x;
 while (x!=‘\0‘){
  if (x==‘A‘){
   cout<<"数据已经增加"<<endl;
   cin>>x;
   continue;}
  else if (x==‘D‘){
   cout<<"数据已经删除"<<endl;
   cin>>x;
   continue;}
  else if (x==‘S‘){
   cout<<"数据已经排序"<<endl;
   cin>>x;
   continue;}
 else {
      cout<<"退出"<<endl; 
   break; }}  
 return 0; 
}

//2-28-(2)
#include <iostream>
using namespace std;
int main()
{
 char x;
 cout<<"Menu: A(dd) D(elete) S(ort) Q(uit),Select one:"<<endl;
 cin>>x;
 switch(x){
  case ‘A‘:
   cout<<"数据已经增加"<<endl;
   continue;
  case ‘D‘:
   cout<<"数据已经删除"<<endl;
   continue;
  case ‘S‘:
   cout<<"数据已经排序"<<endl;
   continue;
  default:
      cout<<"退出"<<endl; 
   break;
}
 return 0;
 
}

\\2-29-1

#include<iostream>
using namespace std;
int main()
{
   int i,n;
    for(i=2;i<=100;i++)
    {
        for(n=2;n<i;n++)
        {
            if(i%n==0)
            break;
        }
        if(i==n)
        cout<<i<<endl;
    }
    return 0;
}

\\2-29-2

#include<iostream>
using namespace std;
int main()
{
   int i,n;
    i=2;
    while(i<=100)
    {
        n=2;
        while(n<=i)
        {
            if(i%n==0)
            break;
            n++;
        }
        if(i==n)
        cout<<i<<endl;
        i++;
    }
    return 0;
}

//2-32-1
#include<iostream>
#include<cstdlib>
using namespace std;
int main(){
cout<<" try to guess my number between 1 to 100"<<endl;
cout<<" i will tell you if your number is bigger or smaller"<<endl;
int x,y;
x=rand()%100;
cin>>y;
while (y!=x)  {
     if (y>x){
         cout<<"lower"<<endl;
         cin>>y;
     }else{
        cout<<"higher"<<endl;
  cin>>y;}}     
cout<<"you are right"<<endl;    
return 0;    
}

//2-32-2
#include<iostream>
#include<cstdlib>
using namespace std;
int main(){
cout<<" try to guess my number between 1 to 100"<<endl;
cout<<" i will tell you if your number is bigger or smaller"<<endl;
int x,y;
x=rand()%100;
do {
cin>>y;
     if (y>x){
 
         cout<<"lower"<<endl;
     }else{
        cout<<"higher"<<endl;}}
while (y!=x) ;       
cout<<"you are right"<<endl;    
return 0;    
}

//2-34
#include<iostream>
using namespace std;
int main(){
    enum color{red,yellow,blue,whilt,black};
    color p;
 int x,y,z,n=0;
 for(x=red;x<=black;x++)
    for(y=x+1;y<=black;y++)
        for(z=y+1;z<=black;z++)
         if(x!=y&&x!=z&&y!=z)
         n++;
 cout<<"totlly "<<n<<" kinds of diffrent conditions"<<endl;     
return 0;    
}

实验总结：

本章节的学习是面向过程的编程，大部分语法与c语言相同，for /while/do while/switch/。同一个题目可由不同算法与不同语法来完成，要找到最高效简洁的方法。本次编程练习中，在输出质数一环节出现卡顿，尤其在使用do while语法时，未成功运行。而在随机数一环节，由于使用的是伪随机数函数，虽然成功运行，但失去了程序的乐趣性。