getline

error in getline input in c++ [duplicate]

由 ♀尐吖头ヾ 提交于 2020-08-09 07:13:09
问题 This question already has answers here : Why does std::getline() skip input after a formatted extraction? (3 answers) Closed 5 years ago . Hi guys i am facing an unknown error while taking input from getline.My purpose is to take a number and two strings as input from the user and print the first string.Here is the problem code #include <iostream> using namespace std; int main() { int t; cin>>t; while(t--) { string s,p; getline(cin,s); getline(cin,p); cout<<s; } return 0; } Now when i give

getline to read in a string that has both white spaces and is comma seperated

由 心已入冬 提交于 2020-06-29 06:32:05
问题 Okay, so i have a file that has a string like so: 10/11/12 12:30 PM,67.9,78,98 ... ... I want to separate it like so 10/11/12 12:30 PM 67.9 I know you use getline to separate the comma separated stuff: getline(infile, my_string, ',') but I also know that doing this to get the date: getline(infile, my_string, ' ') would read in the spaces into my_string so is there any other way to go about this? Also, what would I need to do to skip over the last 2 (78,98) and go to the next line? Would just

Used .ignore('\n') and the Getline function that follows is only taking half of the input from file

由 冷暖自知 提交于 2020-06-09 05:24:06
问题 I tried to make sure what I'm asking wasn't a duplicate since this must be a very beginner mistake but I couldn't find something similar but if someone has a reference to a similar post that'd be great as well anyways So I'm trying to make a battleship game that reads in the ship placement from a .csv file but before it places the ships it goes through the file and makes sure all the ships are found in the file. The data in the file is formatted as follows: Carrier,B2,H Battleship,D4,V

Trying to use int in getline

由 ↘锁芯ラ 提交于 2020-05-25 07:24:42
问题 cout << "How many questions are there going to be on this exam?" << endl; cout << ">>"; getline(cin, totalquestions); This small piece of code comes from a function in a class that I have created and I need totalquestions to be an int so that it can run through a for loop and keep asking the total amount of questions that I have asked. question q; for(int i = 0; i < totalquestions; i++) { q.inputdata(); questions.push_back(q); } Where does this piece of code comes to play? Does anyone have

C++: Using ifstream with getline();

由 女生的网名这么多〃 提交于 2020-05-09 19:17:25
问题 Check this program ifstream filein("Hey.txt"); filein.getline(line,99); cout<<line<<endl; filein.getline(line,99); cout<<line<<endl; filein.close(); The file Hey.txt has alot of characters in it. Well over a 1000 But my question is Why in the second time i try to print line. It doesnt get print? 回答1: According to the C++ reference (here) getline sets the ios::fail when count-1 characters have been extracted. You would have to call filein.clear(); in between the getline() calls. 回答2: The

Why won't getline function work multiple times in a for loop with an array of structures? [duplicate]

由 醉酒当歌 提交于 2020-04-14 08:04:52
问题 This question already has answers here : Why does std::getline() skip input after a formatted extraction? (3 answers) Closed 4 years ago . I have a little problem. I've created a program that asks user to enter part's name and part's price for four diffrent parts. Each name and price fills a structure, and I have an array of four structures. When i do a for loop to fill all the names and prices, my getline functon doesn't work properly, it simply just skipps the entering part after I enter

Why is cin.ignore() necessary when using “getline” after “cin”, but is not required when using “cin” multiple times?

由 醉酒当歌 提交于 2020-04-06 21:27:08
问题 In my knowledge when using getline() after cin , we need to flush the newline character in the buffer first, before calling getline() , and we do this by calling cin.ignore() . std::string name, address; std::cin >> name; std::cin.ignore(); //flush newline character getline(std::cin,address); But when using multiple cin , we do not need to flush the newline character. std::string firstname, lastname; std::cin >> firstname; std::cout << firstname << std::endl; //no need to flush newline

getline函数

由 拈花ヽ惹草 提交于 2020-03-04 18:16:06
如果希望能在最终输入的字符串中保留输入的空格符，这时候应该用 getline(cin,string) 函数从给定的输入流中读取内容，至到遇到换行符为止（注意换行符也被读进来了），然后把所读内容存入那个string对象中去（注意不存换行符） int main() { string line; //每次读入一整行，直到到达文件末尾 while (getline(cin, line)) cout << line << endl; return 0; } 来源： CSDN 作者： hejiegoubao 链接： https://blog.csdn.net/hejiegoubao/article/details/104657073

（9）awk getline用法详解

由 岁酱吖の 提交于 2020-03-01 17:28:06
getline用法详解 除了可以从标准输入或非选项型参数所指定的文件中读取数据，还可以使用getline从其它各种渠道获取需要处理的数据，它的用法有很多种。 getline的返回值： 如果可以读取到数据，返回1 如果遇到了EOF，返回0 如果遇到了错误，返回负数。如-1表示文件无法打开，-2表示IO操作需要重试(retry)。在遇到错误的同时，还会设置 ERRNO 变量来描述错误 为了健壮性，getline时强烈建议进行判断。例如： 上面的getline的括号尽量加上，因为 getline < 0 表示的是输入重定向，而不是和数值0进行小于号的比较。 无参数的getline getline无参数时，表示从当前正在处理的文件中立即读取下一条记录保存到$0中，并进行字段分割，然后继续执行后续代码逻辑。 此时的getline会设置NF、RT、NR、FNR、$0和$N。 next也可以读取下一行。 getline：读取下一行之后，继续执行getline后面的代码 next：读取下一行，立即回头awk循环的头部，不会再执行next后面的代码 它们之间的区别用伪代码描述，类似于： # next exec 9<> filename while read -u 9 line;do ...code... continue # next ...code... # 这部分代码在本轮循环当中不再执行

Awk基本入门[6] Additional Awk Commands 5

由 做~自己de王妃 提交于 2020-02-14 19:00:58
1、System Function You can use the system built-in function to execute system commands. Please note that there is a difference between two way communication and system command. In "|&", you can pass the output of any awk command as input to an external command, and you can receive the output from the external command in your awk program (basically it is two way communication). Using the system command, you can pass any string as a parameter, which will get executed exactly as given in the OS command line, and the output will be returned (which is not same as the two way communication). The
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