This fragment of the code :
for (int z=0; z<=size; z++)
{
vector<double>::iterator iter = min_element(diff.begin(), diff.end());

//itr = min_element( diff.begin(), diff.end() );
cout<<*iter;
int t3 = iter+1;
int t4 = iter-1;
cout<<"The upper Energy value :"<<energy.at(t3)<<endl;
cout<<"the lower Energy value : "<<energy.at(t4)<<endl;

}//end of the for statement for the min

Gives the following error:
cannot convert
`__gnu_cxx::__normal_iterator<double*, std::vector<double, std::allocator<double> > >' to `int' in initialization

Does anyone have any idea about this error?
Raj