题解 | 糟糕的打谱员

#include <bits/stdc++.h>
using namespace std;
using ll = long long int;
using ld = long double;
using PII=pair<ll,ll>;
using PIII=pair<int,pair<int,int>>;
const ld ESP = 1e-10;
const ld PI = acosl(-1);
const int N=1e6+10;
const int M=2e5+10;
// const int mod = 1000000007;
const int mod = 998244353;
//随机化
random_device rd;
mt19937 gen(rd());
uniform_int_distribution<> dis(1, 1000000000);

void solve(){
    int n;
    cin>>n;
    int c[n+1],x[n+1];
    for(int i=1;i<=n;i++){
        cin>>c[i]>>x[i];
    }
    vector<int> dp(n+1,1);
    vector<vector<int>> g(2,vector<int>(11,0));
    int ans=0;
    for(int i=1;i<=n;i++){
        for(int j=1;j<=10;j++){
            if(j!=x[i])dp[i]=max(1+g[c[i]^1][j],dp[i]);
        }
        g[c[i]][x[i]]=max(g[c[i]][x[i]],dp[i]);
        // cout<<dp[i]<<" ";
        ans=max(ans,dp[i]);
    }
    // cout<<'\n';
    cout<<ans<<'\n';

}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int _=1;
    cin>>_;
    while(_--){
        solve();
    }
    return 0;
}