求解：第二组数无法输入

#include <iostream>
#include <vector>

using namespace std;

int main()
{
    vector<int> ivec1,ivec2;
    int num1,num2;
   
    cout<<"Enter the first series of numbers:"<<endl;
    while(cin>>num1)
        ivec1.push_back(num1);
        
    cout<<"Enter the second series of numbers:"<<endl;
    while(cin>>num2)
        ivec2.push_back(num2);
        
    vector<int>::iterator it=ivec1.end()<ivec2.end()?ivec1.end():ivec2.end();
    for(vector<int>::iterator it1=ivec1.begin();it1!=it;++it1)
        for(vector<int>::iterator it2=ivec2.begin();it2!=it;++it2)
        {
            if(*it1!=*it2)
                {cout<<"false!"<<endl;
                return -1;
                }
            else{
                 cout<<"ture!"<<endl;
                 if(ivec1.end()<ivec2.end())
                     cout<<"The first numbers are parts of second numbers"<<endl;
                 else if(ivec1.end()==ivec2.end())
                      cout<<"The first numbers are equle to second numbers"<<endl;
                 else
                     cout<<"The second numbers are parts of first numbers"<<endl;
                     
                 return 0;
                 }
        }
}