隨機化字符輸出到文本文件

Question

我很新的C++編程，我想顯示

如何以這種格式顯示產生output.txt文件。

A B C d E F G H I J K L M N 2 O P Qř式T U V W X arrow-

T W＆ģX Z R L L N H A我A F L E W^g^Q H V RÑV dù

在文本文件

，但我不知道爲什麼它們顯示爲垃圾。

#include <iostream> 
#include <cstdlib> 
#include <ctime> 
#include <fstream> 
using namespace std; 


void random (std::ostream& output) 
{ 
    int letter[26]; 
    int i,j,temp; 

    srand(time(NULL)); 


     for(i=0; i<26; i++) 
      { 
       letter[i] = i+1; 
       output<<(char)(letter[i]+'A'-1)<<" "; 
//by ending endl here i am able to display but the letter will display in horizontal which is not what i wanted  

      }  

     for(i=0; i<26; i++) 
     { 
      j=(rand()%25)+1; 
      temp = letter[i]; 
      letter[i] = letter[j]; 
      letter[j] = temp; 
      output<<((char) (letter[i]+'A'-1))<<" "; 
     } 



} 

Answer 1

void random (std::ostream& output) 
{ 
    int letter[26]; 
    int i,j,temp; 

    srand(time(NULL)); 


     for(i=0; i<26; i++) 
     { 
      letter[i] = i+1; 
      output<<(char)(letter[i]+'A'-1)<<" ";  

     }  
     output << "\n";  //that's all what you need 
     for(i=0; i<26; i++) 
     { 
      j=(rand()%25)+1; 
      temp = letter[i]; 
      letter[i] = letter[j]; 
      letter[j] = temp; 
      output<<((char) (letter[i]+'A'-1))<<" "; 
     } 



} 

未來 - 不使用std :: ENDL，因爲它也刷新流緩衝區，這可能是不必要的。改用'\ n'。但整個功能可以更簡單：

void random (std::ostream& output) 
{ 
    srand(time(NULL)); 


     for(int i = 65; i < 91; ++i)   // i == 65, because it's A in ASCII 
      output << (char)i << " "; 
     output << "\n";  //that's all what you need 

     for(int i=0; i<26; i++) 
     { 
      output <<((char)(rand()%26 + 65))<<" "; 
     } 
}