Read string with spaces in C++

Question

In this C++ code:

#include<bits/stdc++.h>
using namespace std;

int main()
{
    string S;
    getline(cin,S);
    cout<<S;

    return 0;
}

It prints the string with spaces, eg:

Input:

abc def

Output:

abc def

However, in this code:

#include<bits/stdc++.h>
using namespace std;

int main()
{
    int n;
    cin>>n;
    string S;
    getline(cin,S);
    cout<<S;

    return 0;
}

It does not print any output, eg:

Input:

1
abc def

Output:

How is that even possible? Please help. Where am I going wrong?

score 3 · Answer 1 · answered Jul 19 '18 at 06:15

3

You read a number and then a line. Think carefully about what is going on, a newline is not part of a number. So if the input is 123 newline, you read the number 123 and then getline reads the newline. Whatever is on the next line hasn't been read at all.

answered Jul 19 '18 at 06:15

john

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4
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I have edited the question, there were some formatting issues. Please look at it now. – Saarthak Jul 19 '18 at 06:18
@Saarthak OK, but the answer is the same. – john Jul 19 '18 at 06:23
Your mistake is thinking that each read starts from the next line. That is not true. – john Jul 19 '18 at 06:24
Using cin.ignore() after the number provides the desired solution :) – Saarthak Jul 19 '18 at 06:24
OK, now try your solution on 123 space newline. ignore() only ignores a single character. The complete solution is in the linked answer. – john Jul 19 '18 at 06:25

Read string with spaces in C++

1 Answers1