c语言strncpy函数

#include<iostream>
#include<assert.h>
using namespace std;


char* strncpy(char*desStr,const char *srcStr,int count)
{
    assert(desStr!=NULL && srcStr!=NULL);
    char *address=desStr;
    while(count-- && (*srcStr)!='\0')
        *desStr++=*srcStr++;
    *desStr='\0';    //重点在于最后要加'\0'
    return address;

}

int main()
{
    int n;
    char dest[100];
    char* src="hello,world";
    printf("please input the number you want to copy:");
    scanf("%d",&n);
    strncpy(dest,src,n);
    printf("%s",&dest);
    cout<<endl;
    return 0;


}