Problem: Exchange the odd and even nodes in a linked list.
Given a "head" pointer to a linked list. You are asked to write a C/C++ function to exchange the odd and even nodes in the linked list. For example:
Please follow the type and function definitions below:
typedef struct _Node
Here is my solution, however I have made a little change to make it look like in a C++ style.
#include <iostream>
class Node
{
public:
int value;
Node* next;
public:
static void ExchangeNodes( Node** );
};
void Node::ExchangeNodes(Node** phead)
{
Node* p1 = *phead;
Node* p2;
int tval;
while( p1 )
{
p2 = p1->next;
if ( !p2 )
break;
tval = p1->value;
p1->value = p2->value;
p2->value = tval;
p1 = p2->next;
}
}
// Here is the test code
int main( int argc, char* argv[] )
{
Node* head;
Node* tail;
Node* iter;
head = new Node;
head->value = 1;
head->next = NULL;
tail = head;
for ( int i = 2; i < 8; i++ )
{
iter = new Node;
iter->value = i;
iter->next = NULL;
tail->next = iter;
tail = iter;
}
for( iter = head; iter != NULL; iter = iter->next )
{
std::cout << iter->value << std::endl;
}
Node::ExchangeNodes( &head );
std::cout<< "--------------------" << std::endl;
for( iter = head; iter != NULL; iter = iter->next )
{
std::cout << iter->value << std::endl;
}
return 0;
}
output:
1
2
3
4
5
6
7
--------------------
2
1
4
3
6
5
7