search

搜索一个序列中的第一次出现在二进制谓词实际上是等效的指定元素与相等在元素的特定顺序或组件与组件在给定序列的目标范围内。

template<class ForwardIterator1, class ForwardIterator2>
   ForwardIterator1 search(
      ForwardIterator1 _First1, 
      ForwardIterator1 _Last1,
      ForwardIterator2 _First2, 
      ForwardIterator2 _Last2
   );
template<class ForwardIterator1, class ForwardIterator2, class Predicate>
   ForwardIterator1 search(
      ForwardIterator1 _First1, 
      ForwardIterator1 _Last1,
      ForwardIterator2 _First2, 
      ForwardIterator2 _Last2
      Predicate _Comp
   );

参数

  • _First1
    解决仅向前迭代器的第一个元素的位置在要搜索的范围。

  • _Last1
    解决仅向前的迭代器通过最终元素的位置一在要搜索的范围。

  • _First2
    解决仅向前迭代器的第一个元素的位置在要匹配的大小。

  • _Last2
    解决仅向前的迭代器通过最终元素的位置一在要匹配的大小。

  • _Comp
    定义要满足条件的用户定义的谓词函数对象,如果两个组件要执行视为等效的。 二进制谓词采用两个参数并返回 true ,在满足和 false,在未满足。

返回值

解决仅向前迭代器的第一subsequence的第一个元素的位置二进制谓词实际上是等效的指定与指定的顺序或。

备注

用于的 operator== 确定在元素和指定值之间的匹配必须实施在其操作数之间的等效性关系。

引用的范围必须是有效的;所有指针必须dereferenceable,在每个序列中最后位置以访问按增量。

平均复杂是线性有关所搜索的范围,因此,最糟糕的情况复杂也是线性有关序列的范围内搜索。

示例

// alg_search.cpp
// compile with: /EHsc
#include <vector>
#include <list>
#include <algorithm>
#include <iostream>

// Return whether second element is twice the first
bool twice (int elem1, int elem2 )
{
   return 2 * elem1 == elem2;
}

int main( ) {
   using namespace std;
   vector <int> v1, v2;
   list <int> L1;
   vector <int>::iterator Iter1, Iter2;
   list <int>::iterator L1_Iter, L1_inIter;

   int i;
   for ( i = 0 ; i <= 5 ; i++ )
   {
      v1.push_back( 5 * i );
   }
   for ( i = 0 ; i <= 5 ; i++ )
   {
      v1.push_back( 5 * i );
   }

   int ii;
   for ( ii = 4 ; ii <= 5 ; ii++ )
   {
      L1.push_back( 5 * ii );
   }

   int iii;
   for ( iii = 2 ; iii <= 4 ; iii++ )
   {
      v2.push_back( 10 * iii );
   }

   cout << "Vector v1 = ( " ;
   for ( Iter1 = v1.begin( ) ; Iter1 != v1.end( ) ; Iter1++ )
      cout << *Iter1 << " ";
   cout << ")" << endl;

   cout << "List L1 = ( " ;
   for ( L1_Iter = L1.begin( ) ; L1_Iter!= L1.end( ) ; L1_Iter++ )
      cout << *L1_Iter << " ";
   cout << ")" << endl;

   cout << "Vector v2 = ( " ;
   for ( Iter2 = v2.begin( ) ; Iter2 != v2.end( ) ; Iter2++ )
      cout << *Iter2 << " ";
      cout << ")" << endl;

   // Searching v1 for first match to L1 under identity
   vector <int>::iterator result1;
   result1 = search (v1.begin( ), v1.end( ), L1.begin( ), L1.end( ) );

   if ( result1 == v1.end( ) )
      cout << "There is no match of L1 in v1."
           << endl;
   else
      cout << "There is at least one match of L1 in v1"
           << "\n and the first one begins at "
           << "position "<< result1 - v1.begin( ) << "." << endl;

   // Searching v1 for a match to L1 under the binary predicate twice
   vector <int>::iterator result2;
   result2 = search  (v1.begin( ), v1.end( ), v2.begin( ), v2.end( ), twice );

   if ( result2 == v1.end( ) )
      cout << "There is no match of L1 in v1."
           << endl;
   else
      cout << "There is a sequence of elements in v1 that "
           << "are equivalent\n to those in v2 under the binary "
           << "predicate twice\n and the first one begins at position "
           << result2 - v1.begin( ) << "." << endl;
}
  
  

要求

标头: <algorithm>

命名空间: std

请参见

参考

标准模板库