upper_bound()返回值

函數upper_bound()返回的在前閉後開區間查找的關鍵字的上界，如一個數組number序列1,2,2,4.upper_bound(2)後，返回的位置是3（下標）也就是4所在的位置,同樣，如果插入元素大於數組中全部元素，返回的是last。（注意：此時數組下標越界！！）

返回查找元素的最後一個可安插位置，也就是“元素值>查找值”的第一個元素的位置

測試代碼如下：

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

void main()
{
    const int VECTOR_SIZE = 8 ;

    // Define a template class vector of int
    typedef vector<int, allocator<int> > IntVector ;

    //Define an iterator for template class vector of strings
    typedef IntVector::iterator IntVectorIt ;

    IntVector Numbers(VECTOR_SIZE) ;

    IntVectorIt start, end, it, location, location1;

    // Initialize vector Numbers
    Numbers[0] = 4 ;
    Numbers[1] = 10;
    Numbers[2] = 10 ;
    Numbers[3] = 30 ;
    Numbers[4] = 69 ;
    Numbers[5] = 70 ;
    Numbers[6] = 96 ;
    Numbers[7] = 100;

    start = Numbers.begin() ;   // location of first
                                // element of Numbers

    end = Numbers.end() ;       // one past the location
                                // last element of Numbers

    // print content of Numbers
    cout << "Numbers { " ;
    for(it = start; it != end; it++)
        cout << *it << " " ;
    cout << " }\n" << endl ;

    //return the last location at which 10 can be inserted
    // in Numbers
    location = lower_bound(start, end, 9) ;
	location1 = upper_bound(start, end, 10) ;

    cout << "Element 10 can be inserted at index "
        << location - start<< endl ;
	 cout << "Element 10 can be inserted at index "
        << location1 - start<< endl ;
}