set::lower_bound, set::upper_bound, 和 set::equal_range
在 Visual C++ 演示如何使用 设置:: lower_bound,设置:: upper_bound, 和 设置:: equal_range 标准 (STL)模板库函数。
template<class _K, class _Pr, class _A>
class set
{
public:
// Function 1:
const_iterator lower_bound(const _K& _Kv) const;
// Function 2:
const_iterator upper_bound(const _K& _Kv) const;
// Function 3:
_Paircc equal_range(const _K& _Kv) const;
}
备注
备注
类/参数名在原型不匹配版本在头文件。修改某些提高可读性。
lower_bound 函数返回迭代器对具有一个键不符合该值传递给 lower_bound 功能的控件序列的最早的元素。 upper_bound 函数返回迭代器对具有与该值的密钥传递给 upper_bound 功能的控件序列的最早的元素。 如果该元素不存在，则函数返回 结束。 在两种情况下，功能 set::key_comp(key，其中 *x)*用于确定键是否匹配。 equal_range 函数返回值对，。First 是 lower_bound 函数的结果，因此， .second 是 upper_bound 函数的结果。
示例
// SetBoundRange.cpp
// compile with: /EHsc
//
// Illustrates how to use the lower_bound function to get an
// iterator to the earliest element in the controlled sequence
// that has a key that does not match the value passed to the
// function. It also illustrates how to use the upper_bound
// function to get an iterator to the earliest element in the
// controlled sequence that has a key that matches the value
// passed to the function. The last thing it illustrates is
// how to use the equal_range function to get a pair value that
// contains the lower_bound and upper_bound results of the key.
//
// Functions:
//
// lower_bound Returns an iterator whose value does not match the
// key passed to the function, or end() if no such
// element exists.
// upper_bound Returns an iterator whose value matches the key
// passed to the function, or end() if no such element
// exists.
// equal_range Returns a pair of (lower_bound,upper_bound).
//////////////////////////////////////////////////////////////////////
#pragma warning(disable:4786)
#include <set>
#include <iostream>
using namespace std ;
typedef set<int> SET_INT;
int main() {
SET_INT s1;
SET_INT::iterator i;
cout << "s1.insert(5)" << endl;
s1.insert(5);
cout << "s1.insert(10)" << endl;
s1.insert(10);
cout << "s1.insert(15)" << endl;
s1.insert(15);
cout << "s1.insert(20)" << endl;
s1.insert(20);
cout << "s1.insert(25)" << endl;
s1.insert(25);
cout << "s1 -- starting at s1.lower_bound(12)" << endl;
// prints: 15,20,25
for (i=s1.lower_bound(12);i!=s1.end();i++)
cout << "s1 has " << *i << " in its set." << endl;
cout << "s1 -- starting at s1.lower_bound(15)" << endl;
// prints: 15,20,25
for (i=s1.lower_bound(15);i!=s1.end();i++)
cout << "s1 has " << *i << " in its set." << endl;
cout << "s1 -- starting at s1.upper_bound(12)" << endl;
// prints: 15,20,25
for (i=s1.upper_bound(12);i!=s1.end();i++)
cout << "s1 has " << *i << " in its set." << endl;
cout << "s1 -- starting at s1.upper_bound(15)" << endl;
// prints: 20,25
for (i=s1.upper_bound(15);i!=s1.end();i++)
cout << "s1 has " << *i << " in its set." << endl;
cout << "s1 -- s1.equal_range(12)" << endl;
// does not print anything
for (i=s1.equal_range(12).first;i!=s1.equal_range(12).second;i++)
cout << "s1 has " << *i << " in its set." << endl;
cout << "s1 -- s1.equal_range(15)" << endl;
// prints: 15
for (i=s1.equal_range(15).first;i!=s1.equal_range(15).second;i++)
cout << "s1 has " << *i << " in its set." << endl;
}
Output
s1.insert(5)
s1.insert(10)
s1.insert(15)
s1.insert(20)
s1.insert(25)
s1 -- starting at s1.lower_bound(12)
s1 has 15 in its set.
s1 has 20 in its set.
s1 has 25 in its set.
s1 -- starting at s1.lower_bound(15)
s1 has 15 in its set.
s1 has 20 in its set.
s1 has 25 in its set.
s1 -- starting at s1.upper_bound(12)
s1 has 15 in its set.
s1 has 20 in its set.
s1 has 25 in its set.
s1 -- starting at s1.upper_bound(15)
s1 has 20 in its set.
s1 has 25 in its set.
s1 -- s1.equal_range(12)
s1 -- s1.equal_range(15)
s1 has 15 in its set.
要求
**标题:**set