https://www.acwing.com/activity/content/competition/problem_list/2193/

4603. 最大价值

#include<bits/stdc++.h>
using namespace std;
int main(void)
{
    int t; cin>>t;
    while(t--)
    {
        int n; cin>>n;
        string s; cin>>s;
        int temp=0,sum=0;
        for(int i=s.size()-1;i>=0;i--)
        {

            if(s[i]=='A') sum=max(sum,temp);
            if(s[i]=='P') temp++;
            else temp=0;
        }
        cout<<sum<<endl;
    }
    return 0;
}

4604. 集合询问

#include<bits/stdc++.h>
using namespace std;
map<string,int>mp;
int main(void)
{
    int t; cin>>t;
    while(t--)
    {
        char op; cin>>op;
        string s; cin>>s;
        reverse(s.begin(),s.end());
        while(s.size()<20) s=s+"0";
        string ans;
        for(int i=0;i<s.size();i++) 
        {
            int temp=s[i]-'0';
            ans+=to_string(temp%2);
        }
        if(op=='+') mp[ans]++;
        else if(op=='-') mp[ans]--;
        else cout<<mp[ans]<<'\n';
    }
    return 0;
}