STL_算法_替换(replace、replace_copy、replace_if、replace_copy_if)
C++ Primer 学习中。。。
简单记录下我的学习过程 (代码为主)
所有容器适用
replace(b,e,ov,nv) //把oldvalue替换成newvalue
replace_if(b,e,p,v) //把符合p条件的替换成v
replace_copy(b1,e1,b2,ov,nv)
replace_copy_if(b1,e1,b2,p,v)
/**------http://blog.csdn.net/u010579068------**/
#include
#include
#include
#include
#include
#include
#include
using namespace std;
/*****************************************
//所有容器适用
replace(b,e,ov,nv) //把oldvalue替换成newvalue
replace_if(b,e,p,v) //把符合p条件的替换成v
replace_copy(b1,e1,b2,ov,nv)
replace_copy_if(b1,e1,b2,p,v)
*****************************************/
/**----------------------------------------------------------------------------------
----------------------------------------------------------------------------------**/
/*************************************************************************************
std::replace 所有排序容器适用 algorithm
--------------------------------------------------------------------------------------
template < class ForwardIterator, class T >
void replace ( ForwardIterator first, ForwardIterator last,
const T& old_value, const T& new_value );
//eg：
template < class ForwardIterator, class T >
void replace ( ForwardIterator first, ForwardIterator last,
const T& old_value, const T& new_value )
{
for (; first != last; ++first)
if (*first == old_value) *first=new_value;
}
*************************************************************************************/
/*************************************************************************************
std::replace_if 所有排序容器适用 algorithm
--------------------------------------------------------------------------------------
template < class ForwardIterator, class Predicate, class T >
void replace_if ( ForwardIterator first, ForwardIterator last,
Predicate pred, const T& new_value );
//eg：
template < class ForwardIterator, class Predicate, class T >
void replace_if ( ForwardIterator first, ForwardIterator last,
Predicate pred, const T& new_value )
{
for (; first != last; ++first)
if (pred(*first)) *first=new_value;
}
*************************************************************************************/
/*************************************************************************************
std::replace_copy 所有排序容器适用 algorithm
--------------------------------------------------------------------------------------
template < class InputIterator, class OutputIterator, class T >
OutputIterator replace_copy ( InputIterator first, InputIterator last,
OutputIterator result,
const T& old_value, const T& new_value );
//eg：
template < class InputIterator, class OutputIterator, class T >
OutputIterator replace_copy ( InputIterator first, InputIterator last,
OutputIterator result, const T& old_value, const T& new_value )
{
for (; first != last; ++first, ++result)
*result = (*first==old_value)? new_value: *first;
return result;
}
*************************************************************************************/
/*************************************************************************************
std::replace_copy_if 所有排序容器适用 algorithm
--------------------------------------------------------------------------------------
template < class InputIterator, class OutputIterator, class Predicate, class T >
OutputIterator replace_copy_if ( InputIterator first, InputIterator last,
OutputIterator result, Predicate pred,
const T& new_value );
//eg：
template < class InputIterator, class OutputIterator, class Predicate, class T >
OutputIterator replace_copy_if ( InputIterator first, InputIterator last,
OutputIterator result, Predicate pred,
const T& new_value )
{
for (; first != last; ++first, ++result)
*result = (pred(*first))? new_value: *first;
return result;
}
*************************************************************************************/
int main()
{
int myints[] = { 10, 20, 30, 30, 20, 10, 10, 20 };
vector myvector (myints, myints+8); // 10 20 30 30 20 10 10 20
//replace(b,e,ov,nv)
replace (myvector.begin(), myvector.end(), 20, 99); // 10 99 30 30 99 10 10 99
cout << "myvector contains:";
for (vector::iterator it=myvector.begin(); it!=myvector.end(); ++it)
cout << " " << *it;
cout << endl;
/**--------------------------------------------------------------------------------**/
myvector.clear();
vector::iterator it;
// set some values:
for (int i=1; i<10; i++) myvector.push_back(i); // 1 2 3 4 5 6 7 8 9
replace_if (myvector.begin(), myvector.end(), bind2nd(modulus(),2), 0); // 0 2 0 4 0 6 0 8 0
cout << "myvector contains:";
for (it=myvector.begin(); it!=myvector.end(); ++it)
cout << " " << *it;
cout << endl;
/**--------------------------------------------------------------------------------**/
// int myints[] = { 10, 20, 30, 30, 20, 10, 10, 20 };
list mylist (8);
replace_copy (myints, myints+8, mylist.begin(), 20, 66);
cout << "mylist contains: ";
for (list::iterator it=mylist.begin(); it!=mylist.end(); ++it)
cout << " " << *it;
cout << endl;
/**--------------------------------------------------------------------------------**/
deque first,second;
deque::iterator id;
// set some values:
for (int i=1; i<10; i++) first.push_back(i); // 1 2 3 4 5 6 7 8 9
second.resize(first.size()); // allocate space
replace_copy_if (first.begin(), first.end(), second.begin(), not1(bind2nd(modulus(),2)), 0);
// 1 0 3 0 5 0 7 0 9
cout << "second contains: ";
for (id=second.begin(); id!=second.end(); ++id)
cout << " " << *id;
cout << endl;
return 0;
}