splitting a string into an array in C++ without using vector

Question

I am trying to insert a string separated by spaces into an array of strings without using vector in C++. For example:

using namespace std;
int main() {
    string line = "test one two three.";
    string arr[4];

    //codes here to put each word in string line into string array arr
    for(int i = 0; i < 4; i++) {
        cout << arr[i] << endl;
    }
}

I want the output to be:

test
one
two
three.

I know there are already other questions asking string > array in C++, but I could not find any answer satisfying my conditions: splitting a string into an array WITHOUT using vector.

Answer 1

It is possible to turn the string into a stream by using the std::stringstream class (its constructor takes a string as parameter). Once it's built, you can use the >> operator on it (like on regular file based streams), which will extract, or tokenize word from it:

#include <iostream>
#include <sstream>

using namespace std;

int main(){
    string line = "test one two three.";
    string arr[4];
    int i = 0;
    stringstream ssin(line);
    while (ssin.good() && i < 4){
        ssin >> arr[i];
        ++i;
    }
    for(i = 0; i < 4; i++){
        cout << arr[i] << endl;
    }
}

Answer 2

#include <iostream>
#include <sstream>
#include <iterator>
#include <string>

using namespace std;

template <size_t N>
void splitString(string (&arr)[N], string str)
{
    int n = 0;
    istringstream iss(str);
    for (auto it = istream_iterator<string>(iss); it != istream_iterator<string>() && n < N; ++it, ++n)
        arr[n] = *it;
}

int main()
{
    string line = "test one two three.";
    string arr[4];

    splitString(arr, line);

    for (int i = 0; i < 4; i++)
       cout << arr[i] << endl;
}

Answer 3

#define MAXSPACE 25

string line =  "test one two three.";
string arr[MAXSPACE];
string search = " ";
int spacePos;
int currPos = 0;
int k = 0;
int prevPos = 0;

do
{

    spacePos = line.find(search,currPos);

    if(spacePos >= 0)
    {

        currPos = spacePos;
        arr[k] = line.substr(prevPos, currPos - prevPos);
        currPos++;
        prevPos = currPos;
        k++;
    }


}while( spacePos >= 0);

arr[k] = line.substr(prevPos,line.length());

for(int i = 0; i < k; i++)
{
   cout << arr[i] << endl;
}