数组全排列

void perm(int list[], int k, int m){    if (k==m)    {        copy(list,list+m,ostream_iterator<int>(cout," "));        cout<<endl;        return;    }     for (int i=k; i<m; i++)    {        swap(list[k],list[i]);        perm(list,k+1,m);        swap(list[k],list[i]);    }}