Adjust the element position in the given integer array so that the odd number is in the front of the even number.

The method is to use two pointers. The first pointer points to the beginning and increments backward. The second Pointer Points to the end and increments forward.

# Include <stdio. h> # include <stdlib. h> void alter (int data [], int length) {int * head = data, * tail = data + length-1, temp; while (head <tail) {while (head <tail & * head % 2) head ++; // you must also judge head <tail, because the head increment may exceed the value of tail while (head <tail &&! (* Tail % 2) tail --; if (head <tail) {temp = * head; * head = * tail; * tail = temp ;}} void main () {int I, data [10] = {1, 2, 3, 4, 5, 8, 7, 6, 5, 1}; alter (data, 10); for (I = 0; I <10; I ++) printf ("% d \ t", data [I]); getch ();}

The sword means that there is also a good way of writing extensibility on the offer, which is to pass a function pointer to the alter function to determine whether to move.

This decoupling method improves code reusability.