wrong answer的问题求解

Question

#include<bits/stdc++.h>
using namespace std;
template<class T>
class llist{
private:
    T *date;
    int length;
public:
    llist(){};
    void get_length(){
     cout<<length<<endl;
    }
    llist(T a[],int n)
    {
    this->date=new T[n];
    for(int i=0;i<n;i++)
        date[i]=a[i];
    length=n;
    }
    void sett(T a[],int n)
    {
    this->date=new T[n];
    for(int i=0;i<n;i++)
        date[i]=a[i];
    length=n;
    }
    void Delete(int i){
        if(i<1||i>length+1)throw"位置";
        for(int j=i-1;j<length;j++){date[j]=date[j+1];}length--;

    }
     friend ostream & operator <<(ostream & out,const llist &a)
    {
       for(int i=0;i<a.length;i++)
        {
            if(i==0)out<<a.date[i];
            else out<<" "<<a.date[i];
        }
        return out;
    }
    void Insert(T x)//插入
    {
        for(int j=length;j>=2;j--)date[j]=date[j-1];
        date[2-1]=x;
        length++;

    }
    void Locate(T x){
        for(int i=0;i<length;i++)
            {if(date[i]==x)cout<<i+1;}
    }
};
int main(){
   int a[10000];
   int n;
   cin>>n;
   for(int i=0;i<n;i++)cin>>a[i];
   llist<int>mm;
   mm.sett(a,n);
   cout<<mm<<endl;
   mm.Delete(1);
   cout<<mm<<endl;
   mm.get_length();
   mm.Insert(100);
   cout<<mm<<endl;
   mm.Locate(100);
   return 0;
}