Reading m words from a paragraph from n thread ? C++ multithreading ? Not working?

I want read a paragraph by extracting one word at a time using Multithreading . Each thread should read exactly one word and when paragraph ends they should exit peacefully . I know threads shouldn't be used in this way as there is no advantage in that . But I want to do that so that I can check how threads can work sequentially if required . I tried but it looks like the program is reaching deadlock state and not giving any output at all . There are 11 words in the string and I am using 4 threads .

#include <iostream>
#include <mutex>
#include <sstream>
#include <thread>
#include <chrono>
#include <condition_variable>
using namespace std;
stringstream s("Japan US Canada UK France Germany China Russia Korea India Nepal");
int count = 0;
string word;
condition_variable cv;
mutex m;
int i = 0;
bool check_func(int i,int k)
{
    return i == k;
}
void print(int k)
{
  while(count < 11)   // As there are 11 words
  {
     unique_lock<mutex> lk(m);
     int z = k;
     cv.wait(lk,[&]{return check_func(i,z);});            // Line 33
     s >> word;
     cout<<word<<" ";
     i++;
     cv.notify_all();
     count++;
  }
   return;
}
int main() 
{
    thread threads[4];
    for(int i = 0; i < 4; i++)
       threads[i] = thread(print,i);
    for(auto &t : threads)
       t.join();
    return 0;
}