Stringstream parse comma-separated integers - c++

Question

So guys, Actually What I wanna do here is that when I input 3,12,36 the output will be:
3
12
36
But here I have difficulty on how to make it output all the answer. What I have been doing is that when you input 3,12,36 it will output 3 12 only and if you type 3,12,36,48 it will output 3 12 36.
So it will always miss the last integer because my while loop is not correct I guess. but if I change it into
while(output >> life|| output >> ch)
It doesn't work either. I've done a lot of research but it still makes me confused and I'm still stuck on this part.
vector<int> parseInts(string str) {//23,4,56
vector<int>lifeishard;
stringstream output;
string lifeisgood = str;
output.str(lifeisgood);
int life;
char ch;
while(output >> life >> ch){
lifeishard.push_back(life);
//lifeishard.push_back(life2);
//lifeishard.push_back(life3);
}
return lifeishard;
}
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;
}

Answer 1

On your last number, the while loop fails because there's no character at the end. Just the end of the string. So it doesn't execute the push_back inside the loop.
Change it so that the while loop just gets the number. Then do the push_back in the loop. Then in the loop, after the push, get the comma character. Don't bother checking for failure getting the comma because when it goes around the while loop again it will fail and exit.
I changed to using getline in your main. I changed your loop index to size_t because it is never a good idea to mix signed and unsigned integers, and whenever you use a size() function, it's a size_t. When posting your program it really should include everything. My fixed up version of your program:
#include <vector>
#include <string>
#include <iostream>
#include <sstream>
using namespace std;
vector<int> parseInts(string str) {//23,4,56
vector<int>lifeishard;
stringstream output;
string lifeisgood = str;
output.str(lifeisgood);
int life;
char ch;
while(output >> life){
lifeishard.push_back(life);
output >> ch;
}
return lifeishard;
}
int main() {
string str;
getline(cin, str);
vector<int> integers = parseInts(str);
for(size_t i = 0; i < integers.size(); i++) {
cout << integers[i] << "\n";
}
// Here is how we do for loops over containers in modern C++
for(auto x: integers) {
cout << x << '\n';
}
return 0;
}

Answer 2

A combination of stringstream, getline with delimiter and stoi would be enough for the conversion:
From the C++ reference for getline with delimiter:
Extracts characters from is and stores them into str until the delimitation character delim is found.
With this in mind, the code example below assumes the input is well-formed:
Example
#include <iostream>
#include <sstream>
#include <string>
#include <vector>
using namespace std;
vector<int> parseInts(const string& str, const char delim = ',')
{
vector<int> parsed;
stringstream ss(str);
string s;
while (getline(ss, s, delim)) // <- stores input in s upon hitting delimiter
parsed.push_back(stoi(s)); // <-- convert string to int and add it to parsed
return parsed;
}
int main()
{
string str = "3,12,36"; // <-- change to cin if you'd like
vector<int> ints = parseInts(str);
for (auto& i : ints)
cout << i << "\n";
}
Output
3
12
36
See more: getline, stoi