std::min

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C++
 
算法库
功能
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Functions
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修改序列操作
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Non-modifying sequence operations
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all_of
any_of
none_of		（C++11）
（C++11）
（C++11）
for_each
count
count_if
mismatch
equal
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Modifying sequence operations
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Partitioning operations
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is_partitioned（C++11）
partition
partition_copy（C++11）
排序操作（排序的区间）
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Sorting operations (on sorted ranges)
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is_sorted（C++11）
is_sorted_until（C++11）
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二进制搜索操作（排序的区间）
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Binary search operations (on sorted ranges)
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Set operations (on sorted ranges)
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堆的操作
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Heap operations
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最小/最大操作
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Minimum/maximum operations
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max
max_element
min
min_element
minmax（C++11）
minmax_element（C++11）
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Numeric operations
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C library
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Defined in header <algorithm>
template< class T >
const T& min( const T& a, const T& b );
 (1)
template< class T, class Compare >
const T& min( const T& a, const T& b, Compare comp );
 (2)
template< class T >
T min( std::initializer_list<T> ilist);
 (3) （C++11 起）
template< class T, class Compare >
T min( std::initializer_list<T> ilist, Compare comp );
 (4) （C++11 起）
1-2)
返回两个值中的较小者的.
Original:
Returns the smaller of the two values.
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3-4)
返回最小的值初始化列表中的ilist.
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Returns the smallest of the values in initializer list ilist.
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（1,3）版本使用operator<的值进行比较，（2,4）版本使用给定的比较函数comp
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The (1,3) versions use operator< to compare the values, the (2,4) versions use the given comparison function comp.
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目录

[编辑] 参数

a, b -
值进行比较
Original:
the values to compare
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ilist -
初始化列表中的值进行比较
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initializer list with the values to compare
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cmp - comparison function which returns ​true if if a is less than b.

The signature of the comparison function should be equivalent to the following:

bool cmp(const Type1 &a, const Type2 &b);

The signature does not need to have const &, but the function must not modify the objects passed to it.
The types  Type1 and  Type2 must be such that an object of type T can be implicitly converted to both of them. ​

Type requirements
-
T must meet the requirements of LessThanComparable. for the overloads (1) and (3)
-
T must meet the requirements of CopyConstructible. for the overloads (3) and (4)

[编辑] 返回值

1-2)
较小的a和b。如果这两个值是相等的，返回a.
Original:
The smaller of a and b. If the values are equivalent, returns a.
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3-4)
ilist中的最小值。如果有多个值相当于最小，最左边的值返回.
Original:
The smallest value in ilist. If several values are equivalent to the smallest, returns the leftmost such value.
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[编辑] 复杂性

1-2)
常数
Original:
Constant
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3-4)
线性ilist.size()
Original:
Linear in ilist.size()
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[编辑] 可能的实现

First version 
template<class T> 
const T& min(const T& a, const T& b)
{
    return (a < b) ? a : b;
}
Second version 
template<class T, class Compare> 
const T& min(const T& a, const T& b, Compare comp)
{
    return (comp(a, b)) ? a : b;
}
Third version 
template<class T>
T min( std::initializer_list<T> ilist)
{
    return *std::min_element(ilist.begin(), ilist.end());
}
Fourth version 
template<class T, class Compare>
T min(std::initializer_list<T> ilist, Compare comp)
{
    return *std::min_element(ilist.begin(), ilist.end(), comp);
}

[编辑] 为例

#include <algorithm>
#include <iostream>
 
int main()
{
    std::cout << "smaller of 1 and 9999: " << std::min(1, 9999) << '\n';
    std::cout << "smaller of 'a' and 'b': " << std::min('a', 'b') << '\n';
    std::cout << "smaller of 3.5 and 2.5: " << std::min(3.5, 2.5) << '\n';
}

Output: 

smaller of 1 and 9999: 1
smaller of 'a' and 'b': a
smaller of 3.5 and 2.5: 2.5
本节是不完整的

[编辑] 另请参阅
返回较大的两个元素
Original:
returns the larger of two elements
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（函数模板） [edit]
（C++11）
返回的较大和较小的两个元素
Original:
returns the larger and the smaller of two elements
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（函数模板） [edit]
返回的范围内的最小元素
Original:
returns the smallest element in a range
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（函数模板） [edit]
来自“http://zh.cppreference.com/mwiki/index.php?title=cpp/algorithm/min&oldid=27960”