A Error in C++ primer English Fourth edition

#include<iostream> 
#include<vector>
using namespace std; 

int main() 
...{ 
   vector<int> vec(10,12);
   for(vector<int>::iterator iter=vec.begin();iter!=vec.end();++iter)
       cout<<*iter<<"  ";
   cout<<endl;
   
// The following segment has problem.
// The while loop will not end.
   vector<int>::iterator first=vec.begin();
   while(first!=vec.end())
   ...{
     first=vec.insert(first,42);
     ++first;
   }
   for(vector<int>::iterator iter=vec.begin();iter!=vec.end();++iter)
       cout<<*iter<<"  ";
   cout<<endl;
    
    return   0; 
} 

 Tonight I found a small error in C++ primer fourth. See the above code segment.