dp解的题，空间优化了 ，t了五组数据 ，该如何优化呢？

#include<bits/stdc++.h>
using namespace std;
int dp[2][100005],a[100005],b[100005];
int main()
{
    int n;
    cin >> n;
    for (int i = 1; i <= n;cin>>a[i++]);
    for (int j = 1; j <= n; cin >> b[j++]);
    for(int i=1;i<=n;++i)
        for (int j = 1; j <= n; ++j)
            if (a[i] == b[j]) 
                dp[i%2][j] = dp[i%2==0?1:0][j - 1] + 1;
            else
                dp[i%2][j] = max(dp[i % 2 == 0 ? 1 : 0][j], dp[i % 2][j - 1]);
    cout << dp[n%2][n];
    return 0;
}