StringStream C++ HackerRank Solution
In this challenge, we work with string streams.
stringstream is a stream class to operate on strings. It implements input/output operations on memory (string) based streams. stringstream can be helpful in different type of parsing. The following operators/functions are commonly used here
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Operator >> Extracts formatted data.
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Operator << Inserts formatted data.
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Method str() Gets the contents of underlying string device object.
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Method str(string) Sets the contents of underlying string device object.
Its header file is sstream.
One common use of this class is to parse comma-separated integers from a string (e.g., "23,4,56").
stringstream ss("23,4,56");
char ch;
int a, b, c;
ss >> a >> ch >> b >> ch >> c; // a = 23, b = 4, c = 56
Here ch is a storage area for the discarded commas.
If the >> operator returns a value, that is a true value for a conditional. Failure to return a value is false.
Given a string of comma delimited integers, return a vector of integers.
Function Description
Complete the parseInts function in the editor below.
parseInts has the following parameters:
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string str: a string of comma separated integers
Returns
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vector<int>: a vector of the parsed integers.
Note You can learn to push elements onto a vector by solving the first problem in the STL chapter.
Input Format
There is one line of n integers separated by commas.
Sample Input
23,4,56
Sample Output
23
4
56
Solution
#include <sstream>
#include <vector>
#include <iostream>
using namespace std;
vector<int> parseInts(string str) {
vector<int> integers;
stringstream ss(str);
char ch;
int num;
while (ss >> num) {
integers.push_back(num);
ss >> ch; // Read and discard the comma
}
return integers;
}
int main() {
string str;
cin >> str;
vector<int> integers = parseInts(str);
for(int i = 0; i < integers.size(); i++) {
cout << integers[i] << "\n";
}
return 0;
}
