大考能看一下蒟蒻的代码40re的问题吗？

#include <bits/stdc++.h>

#define int long long

using namespace std;

inline int read()
{
	int ww = 0,ee = 1;
	char ch = getchar();
	while (ch < '0' || ch > '9')
	{
		if (ch == '-')
		{
			ee = -1;
		}
		ch = getchar();
	}
	while (ch >= '0' && ch <= '9')
	{
		ww = ww * 10 + ch - '0';
		ch = getchar();
	}
	return ww * ee;
}


void file()
{
	freopen(".in","r",stdin);
	freopen(".out","w",stdout);
}

int T;

int n,m;

const int N = 1000010;
int a[N];

int b[N],l,r;

int s;

int vis[N];

signed main()
{
	T = read();
	while (T--)
	{
		n = read();
		m = read();
		while (m--)
		{
			a[++r] = read();
			if (!vis[a[r]])
			{
				s++;
			}
			b[r] = n;
			vis[a[r]]++;
		}
		while (n-86400 >= b[l])
		{
			vis[b[l]]--;
			if (!vis[b[l]])
			{
				s--;
			}
			l++;
		}
		cout << s << '\n';
	}
	return 0;
}