算法竞赛入门经典： 第四章 函数与递归 4.4变量交换

/*
变量交换
*/

#include <stdio.h>
#include <stdlib.h>

void swap(int a,int b)
{
	int iTemp = a;
	a = b;
	b = iTemp;
}

void swap(int* a,int* b)
{
	int iTemp = *a;
	*a = *b;
	*b = iTemp;
}

//试图交换地址，地址不能改变，发生错误
void swap2(int* a,int* b)
{
	int *t;
	t = a;
	a = b;
	b = t;
}

//试图交换值，但是t没有指向固定变量，指针在使用前必须先赋值
void swap3(int* a,int* b)
{
	int *t;
	*t = *a;
	*a = *b;
	*b = *t;
}

int main(int argc,char* argv[])
{
	int a = 3,b = 4;
	int* pA = &a;
	int* pB = &b;
	//swap(a,b);
	swap(pA,pB);
	//swap2(pA,pB);
	//swap3(pA,pB);
	printf("%d %d\n",a,b);
	system("pause");
	return 0;
}