c++ - getline 跳过第一个输入字符 c++

标签 c++ loops getline

<分区>

所以我制作这个程序已经有一段时间了。我在整个互联网上都看过了,但没有找到有效的解决方案。每次我在 arr[i].question 和 arr[i].answer 中输入我的输入时,它都说我的问题是错误的,但我没有给出问题的答案。我试过使用 cin.ignore()、cin.clear() 和 cin.sync()。我可能一直在错误的地方使用它们,但我不确定。我可能会感到困惑,所以只看代码。

这里是输入格式。

    cin >> count;
cin.ignore();

for(int i =0; i < count; i++){
    cout << "Enter the question.\n" << endl;
    //enter the question

    getline(cin, arr[i].question);
    cin.ignore();

    cout << "Enter the answer.\n" << endl;
    //enter the answer

    getline (cin, arr[i].answer);
    cin.ignore();

}

这是测试你的输出格式。

    for(int j =0; j < count; j++){
    cout << "\n" << arr[j].question << endl;
    getline(cin, userguess);

    if(arr[j].answer.compare(userguess) !=0){
        cout << "Wrong. Keep trying!\n";
        incorrect++;
        total++;
    }
    if(arr[j].answer.compare(userguess) ==0){
        cout << "Nice job. Keep it up!\n";
        correct++;
        total++;
    }

每当我提出问题时,它都不会在控制台中输出问题或让我输入答案。它只是说错了。 请帮忙?

编辑:这里是整个代码:

// final PROJECT.cpp : Defines the entry point for the console application.

#include <iostream>
#include <string>
#include <fstream>
#include <stdlib.h>
#include <cstring>
#include <cstdio>
#include <stdio.h>
#include <tchar.h>
#include <string.h>
#include <cstdlib>

using namespace std;

struct flashcards{
string question;
string answer;
}FC1, FC2, FC3, FC4, FC5, FC6, FC7, FC8, FC9, FC10, FC11, FC12, FC13, FC14, FC15, FC16, FC17, FC18, FC19, FC20;

int _tmain(int argc, _TCHAR* argv[])

{
system ("color 4B");
string userguess;
string again;
flashcards arr[10000];
int count;
float correct=0;
float incorrect=0;
float total=0;
//one major problem, wont accept spaces.
cout<< "Flash Card Runner\n";
cout<< "This program was made by Jacob Malcy\n";
cout<< "Beta 3.8\n";
cout<< "IN ORDER FOR YOU TO HAVE MULTIPLE WORD FLASH CARDS,\n";
cout << "SKIP NUMBER ONE FLASHCARD QUESTION AND ANSWER!\n";
cout<< "This bug is currently being worked on.\n";
cout << "If you happen to have problems conntact Jacob.\n";
int choice;


cout<< "Would you like to create or test? Enter 0 for create and 1 for test.\n";
cin >> choice;
if(choice==0){
    //Creating new deck of cards
cout<< "How many flashcards do you want?\n";
cin >> count;
cin.clear();

for(int i =0; i < count; i++){
    cout << "Enter the question.\n" << endl;
    //enter the question

    getline(cin, arr[i].question);
    cin.ignore();

    cout << "Enter the answer.\n" << endl;
    //enter the answer

    getline (cin, arr[i].answer);
    cin.ignore();

}
}
else if(choice==1){
    //Reading in new file
    cout << "Reading file...\n";

    string line;
    ifstream myfile ("Save.txt");
    if (myfile.is_open())
    {
        count = 0;

        while ( myfile.good () )
        {
            getline (myfile,line);
            arr[count].question = line;
            cout << line << endl;

        getline (myfile,line);
        arr[count].answer = line;
        cout << line << endl;
        count++;

        }

        myfile.close();
    }

    else cout << "Unable to open the file";
}

do
{

for(int j =0; j < count; j++){
    cout << "\n" << arr[j].question << endl;
    getline(cin, userguess);

    if(arr[j].answer.compare(userguess) !=0){
        cout << "Wrong. Keep trying!\n";
        incorrect++;
        total++;
    }
    if(arr[j].answer.compare(userguess) ==0){
        cout << "Nice job. Keep it up!\n";
        correct++;
        total++;
    }


}
cout<< "The number of correct questions answered was: \n" << correct << endl;
cout<<"The number of total questions answered was: " << total <<"\n";
    cout<< "The number of incorrect questions answered was: \n" << incorrect << endl;
    //cout<< total;
    float percent = (correct/total)*100;
    cout<< "The total percent you got right is: \n" << percent << "% correct" << endl;
    system("pause");
    cout << "Would you like to run the quiz again?\n"
    << "Type y or Y to run this again. If not, enter any other letter.\n";
    cin >> again;
    if((again == "y") || (again == "Y")){
    correct=0;
    incorrect=0;
    total=0;
    }

}while((again == "y") || (again == "Y"));

ofstream myfile ("Save.txt");
if (myfile.is_open())
{

    for(int i =0; i <count; i++){

        myfile << arr[i].question << "\n";
        myfile << arr[i].answer << "\n";
    }
    myfile.close();

    }
else cout << "Unable to save file";

cout << "Your finished with the quiz. Goodbye!\n";

system("PAUSE");
return 0;
}

我运行的时候是这样的

    Flash Card Runner
This program was made by Jacob Malcy
Beta 3.8
IN ORDER FOR YOU TO HAVE MULTIPLE WORD FLASH CARDS,
SKIP NUMBER ONE FLASH CARD QUESTION AND ANSWER!
This is a bug is currently being worked on.
if you happen to have problems, conntact Jacob.
Would you like to create or test? Enter 0 for create and 1 for test.

如果我输入零:

How many flashcards do you want?

假设我输入两个 2

Enter the question.

Hi ho
Enter the answer.

Merry oh

enter the question.

fi fa
enter the answer.

fo fum

然后它就跳到:

Wrong. Keep trying!

erry oh

错之前应该显示第一个问题,给我回答的机会。 它只是在我之前说错了。然后它显示缺少第一个字符的答案。给你。

最佳答案

我假设您在 getline 之后立即调用 ignore 以去除尾随的换行符。

不要那样做。 std::getline 已经从流中提取换行符(并丢弃它),因此您将忽略下一行的第一个字符。

关于c++ - getline 跳过第一个输入字符 c++,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/16092356/

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