Question

每次运行程序时，do while循环第一行的输出都会重复。所以输出＆＃34;输入要添加的字符......＆＃34;在每个循环开始时输出两次。如何在每次循环重复时只输出一次？

主档

#include "LinkedList.h"
#include "ListNode.h"
#include "Node.h"
#include <iostream>
#include <stdlib.h>
using namespace std;

LinkedList<char> *setUpSentence() {
    //allocate the linked list objet
    LinkedList<char> *sentence = new LinkedList<char>();
    char ch;
    do {
        cout << "Enter characters to add, enter full stop to finish adding." << endl;
        ch = cin.get();
        sentence->addAtEnd(ch);
    } while (ch != '.');

    return sentence;
}

int main() {

    //call the function, store the returned pointer in sentence variable
    LinkedList<char> *sentence = setUpSentence();

    while(sentence->size > 0) {
        cout << sentence->removeAtFront() << endl;
    }  
    //delete to avoid memory leak
    delete sentence;

}

Answer 1

问题在于ch = cin.get();。它将自动读取输入流中剩余的内容。您需要先使用this清除它。

Answer 2

您的程序正在从标准输入缓冲区读取。阅读更多相关信息＆＃34; What is the standard input buffer?＆＃34;

如果你想重复＆＃34; cout＆＃34;只有一次，重写如下：

char ch;
cout <<"char"<<ch<< "Enter characters to add, enter full stop to finish adding." << endl;
do {
    ch = cin.get();
} while (ch != '.');

while循环每次循环重复两次cout线？

2 个答案: