如下代码65pts

#include<bits/stdc++.h>
#define int long long
using namespace std;
const int N=2e6+1;
int dp[N],a[N],n,pos[N],p[N];
void solve()
{
	cin>>n;
	for(int i=1;i<=n;++i)p[i]=0,pos[i]=-1,a[i]=0,dp[i]=0;
	for(int i=1;i<=n;++i)
	{
		cin>>a[i];
		if(a[i]==a[i-1])p[i]=p[i-1]+a[i];
		else p[i]=p[i-1];
	}
	for(int i=1;i<=n;++i)
	{
		dp[i]=dp[i-1];
		if(pos[a[i]]!=-1)dp[i]=max(dp[i],dp[pos[a[i]]+1]+a[i]+p[i-1]-p[pos[a[i]]]);
		pos[a[i]]=i;
	}
	cout<<dp[n]<<endl;
}
signed main()
{
	//freopen("color3.in","r",stdin);
	//freopen("color3.out","w",stdout);
	int _;cin>>_;
	while(_--)solve();
	return 0;
}

而当我把pos数组的初值改成0时，100pts

有人能解释其原因吗？