C++ list iterator reverse list using while loop

Description

C++ list iterator reverse list using while loop

#include <iostream>
#include <list>
using namespace std;
int main()//from w ww .ja va2 s.c  o m
{
   int j;
   list<int> theList;
   list<int>::iterator iter1;
   list<int>::iterator iter2;
   for(j=2; j<16; j+=2)           //fill list with 2, 4, 6, ...
      theList.push_back(j);
   cout << "Before reversal: ";   //display list
   for(iter1=theList.begin(); iter1 != theList.end(); iter1++)
      cout << *iter1 << " ";
   iter1 = theList.begin();       //set to first element
   iter2 = theList.end();         //set to one-past-last
   --iter2;                       //move to last
   while(iter1 != iter2)
   {
      swap(*iter1, *iter2);       //swap front and back
      ++iter1;                    //increment front
      if(iter1==iter2)            //if even number of elements
         break;
      --iter2;                    //decrement back
   }
   cout << "\nAfter reversal: ";  //display list
   for(iter1=theList.begin(); iter1 != theList.end(); iter1++)
      cout << *iter1 << " ";
   cout << endl;
   return 0;
}



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