线性表代码，为什么运行不了，显示Process exited after 0.3528 seconds with return value 0

Question

#include<iostream>
#include<stdlib.h>
using namespace std; 
class SeqList
{
public:
SeqList(){length=0;}
void Printflist();
void quickSwapList(int a[],int n);
void CreateList();
private:
int *a;
int length;
};
void SeqList::Printflist()
{
for(int i=0;i<length;i++)
{
cout<<a[i]<<"";
}
cout<<endl;
}
void SeqList::quickSwapList(int a[],int n)
{
{
int i=0,j=length-1;
while(i<j)
{
while(a[i]<0&&i<j)i++;
while(a[j]>=0&&i<j)j--;
if(i<j)
{
int t=a[i];
a[i]=a[j];
a[j]=t;    
}    
i++;
j--;
}        
}    
}
void SeqList::CreateList()
{
int n=0,i=0;
cout<<"请输入顺序表长度"<<endl;
cin>>n;
length=n;
a=(int*)malloc(sizeof(int)*n);
for(i=0;i<n;i++)
{
cin>>a[i];
}
}

int main()
{
SeqList L;
int *i;
int j;
L.quickSwapList(i,j);
return 0;
}

Answer 1

int main()
{
SeqList L;
L.createList();
L.quickSwapList();
L.printfList();
return 0;
}

把quickSwapList函数的参数去掉，这个函数不需要参数的