reading multiple lines into arrays

Hello,

I am just starting to solve a problem, with multiple arrays, something like:

2,2
1,2,3,4
6,7,8,9,10
0,2
1,1

+++++
output:
3, 7

first line no of arrays and no of queries. 2nd and 3rd line, array contents. 4th and 5th querirs (i.e 0th array, 2and elem, 1st array, 1st elem)

for that, i what is the good way to read input , ie ,may be use istream_iterator. But follwing startup program fails to compile !

Code:

---

        std::vector<int> vec;

        std::string stringvalues = "125 320 512 750 333";
        std::istringstream iss(stringvalues);

        vec.emplace_back(std::istream_iterator<int>{ iss }, std::istream_iterator<int>{});


---

Error C2440 'initializing': cannot convert from 'initializer list' to 'int'

But when i try :

Code:

---

        std::string stringvalues = "125 320 512 750 333";
        std::istringstream iss(stringvalues);

        std::vector<int> vec(std::istream_iterator<int>{ iss }, std::istream_iterator<int>{});

---

works ok !

thanks a lot for comments and inputs

Pdk

Code:

---

vec.emplace_back(std::istream_iterator<int>{ iss }, std::istream_iterator<int>{});

---

try:

Code:

---

vec.assign(std::istream_iterator<int>{ iss }, std::istream_iterator<int>{});

---

Look it up :)

Thanks a lot kaud.

Sorry for not doing proper home work

I was googling yesterday (reg emplace_back ), and i think i need , vector of vectors for emplace_back to work :

Code:

---


        std::vector<std::vector<int>> vec;

        std::string stringvalues = "125 320 512 750 333";

        std::istringstream iss(stringvalues);

        vec.emplace_back(std::istream_iterator<int>{ iss }, std::istream_iterator<int>{});

---

The above code works now with emplace_back :)