How to store a string with multiple whitespaces c++

Question

My program is supposed to take in some input such as "Hi there." or "I have an a." (notice the ending dot) and output "yes" if the string contains an "a" or "no" if it doesn't. The problem is that cin skips whitespaces and noskipws doesn't seem to work.

The code I've got:

#include <iostream>
#include <string>
using namespace std;


int main() {
    string sequence;
    cin >> noskipws >> sequence;

    for (auto c : sequence) {
        if (c == 'a') {
            cout << "yes" << "\n";
            return 0;
        }
    }
    cout << "no" << "\n";
}

Input: "where are you."   Output: nothing
Input: "what."            Output: yes

Is there anyone around here to explain why `noskipws` doesn't work in OP's example, and why `std::getline()` solves it? — πάντα ῥεῖ, Sep 30 '18 at 08:36

score 0 · Accepted Answer · edited Sep 30 '18 at 07:48

0

Solution using getline(), as πάντα ῥεῖ suggested:

#include <iostream>
#include <string>

int main()
{
    std::string sequence;
    std::getline(std::cin, sequence);

    for (auto c : sequence) {
        if (c == 'a') {
            std::cout << "yes\n";
            return 0;
        }
    }
    std::cout << "no\n";
}

edited Sep 30 '18 at 07:48

Swordfish

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answered Sep 30 '18 at 07:46

Álvaro

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score 0 · Answer 2 · answered Sep 30 '18 at 08:28

You could use std::getline() or you can try this is if you want to select word by word.

#include <iostream>
#include <string>

int main(){
    std::string sequence;
    while(std::cin >> sequence){
        for (auto c : sequence) {
            if (c == 'a') {
                std::cout << "yes\n";
                return 0;
            }
        }
    }
    cout << "no" << "\n";
    return 0;
}

How to store a string with multiple whitespaces c++

2 Answers2