std::search_n

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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
修改序列操作
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Modifying sequence operations
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分区操作
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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）
sort
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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设置操作（排序的区间）
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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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数字操作
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Numeric operations
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C库
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C library
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Defined in header <algorithm>
template< class ForwardIt, class Size, class T >
ForwardIt1 search_n( ForwardIt first, ForwardIt last, Size count, const T& value );
 (1)
template< class ForwardIt, class Size, class T, class BinaryPredicate >

ForwardIt1 search_n( ForwardIt first, ForwardIt last, Size count, const T& value,

                     BinaryPredicate p );
 (2)
为第一序列的计数相同的元件，每个等于给定值的值的范围内搜索[first, last)。的第一个版本使用operator==比较的元素，第二个版本使用给定的二元谓词p.
Original:
Searches the range [first, last) for the first sequence of count identical elements, each equal to the given value value. The first version uses operator== to compare the elements, the second version uses the given binary predicate p.
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目录

[编辑] 参数

first, last -
检查的元素
Original:
the range of elements to examine
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count -
序列的长度，以搜寻
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the length of the sequence to search for
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value -
的元素的值，以搜寻
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the value of the elements to search for
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p - binary predicate which returns ​true if the elements should be treated as equal.

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

bool pred(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 type  Type1 must be such that an object of type ForwardIt can be dereferenced and then implicitly converted to  Type1. The type  Type2 must be such that an object of type T can be implicitly converted to  Type2.

​

Type requirements
-
ForwardIt must meet the requirements of ForwardIterator.

[编辑] 返回值

iiterator范围在[first, last)找到的序列的开头。如果没有发现这样的序列，last返回.
Original:
Iiterator to the beginning of the found sequence in the range [first, last). If no such sequence is found, last is returned.
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[编辑] 复杂性

在最last - first的谓词中的应用.
Original:
At most last - first applications of the predicate.
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[编辑] 可能的实现

First version 
template<class ForwardIt, class Size, class T>
ForwardIt1 search_n(ForwardIt first, ForwardIt last,
                          Size count, const T& value)
{
    Size curr_count = 0;
    ForwardIt result, t_last = first;
    std::advance(t_last, std::distance(first, last) - count + 1);
 
    for (; first != t_last; first++) {
        curr_count = 0;
        result = first;
        while (*first == value) {
            curr_count++;
            if (curr_count == count) {
                return result;
            }
            ++first;
        }
    }
    return last;
}
Second version 
template<class ForwardIt, class Size, class T, class BinaryPredicate>
ForwardIt1 search_n(ForwardIt first, ForwardIt last,
                          Size count, const T& value, BinaryPredicate p)
{
    Size curr_count = 0;
    ForwardIt result, t_last = first;
    std::advance(t_last, std::distance(first, last) - count + 1);
 
    for (; first != t_last; first++) {
        curr_count = 0;
        result = first;
        while (p(*first == value)) {
            curr_count++;
            if (curr_count == count) {
                return result;
            }
            ++first;
        }
    }
    return last;
}

[编辑] 为例

本节是不完整的

[编辑] 另请参阅
发现在一定范围内的最后一个序列中的元素
Original:
finds the last sequence of elements in a certain range
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（函数模板） [edit]


（C++11）
找到的第一个元素，满足特定的标准
Original:
finds the first element satisfying specific criteria
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（函数模板） [edit]
searches for a range of elements
（函数模板） [edit]
来自“http://zh.cppreference.com/mwiki/index.php?title=cpp/algorithm/search_n&oldid=27753”