交换字符串--memcpy()函数--swap()函数

交换字符串--memcpy()函数；

void *memcpy(void *dst, const void *src, size_t n);
//If copying takes place between objects that overlap, the behavior is undefined.

简单字符交换；swap(a,b);

但是对于字符串怎么交换，实际上用复制函数即可；

#include<cstdio>
#include<cstring>
#include<iostream>
using namespace std;
int main(){char a[100],b[100],c[100];cin>>a>>b;	memcpy(c,a,100);memcpy(a,b,100);//a=b;memcpy(b,c,100);cout<<a<<endl<<b<<endl;
}

对于输入输出：

a23 b45
b45
a23--------------------------------
Process exited after 3.71 seconds with return value 0
请按任意键继续. . .

实际上swap函数也能解决；

#include<cstdio>
#include<cstring>
#include<iostream>
using namespace std;
int main(){char a[100],b[100],c[100];cin>>a>>b;	memcpy(c,a,100);memcpy(a,b,100);//a=b;memcpy(b,c,100);cout<<a<<endl<<b<<endl;swap(a,b);cout<<a<<endl<<b<<endl;	 
}

a,b重新交换回来了.. 

a23 b45
b45
a23
a23
b45--------------------------------
Process exited after 3.71 seconds with return value 0
请按任意键继续. . .