Problem: 2050C - Uninteresting Number
Language: java

Solution 1 (runtime: 484 ms):
import java.util.*;

public class C_Uninteresting_Number{
    static HashMap<Integer, Boolean> hm;
    public static boolean func(int num, int two, int three){
        if(num%9==0)return true;
        if(two==0&&three==0)return false;
        if(hm.containsKey(num))return hm.get(num);
        boolean t=false, th=false;
        if(two>0){
            t = func(num+2, two-1, three);
        }
        if(three>0){
            th = func(num+6, two, three-1);
        }
        hm.put(num, t|th);
        return t|th;
    }
    public static void main(String args[]){
        Scanner scn = new Scanner(System.in);
        int t = scn.nextInt();
        while(t-->0){
            String s = scn.next();
            int n = s.length();
            int num = 0;
            int two = 0, three=0;
            for(int i = 0; i < n; i++){
                num += (s.charAt(i)-'0');
                if(s.charAt(i)=='2')two++;
                if(s.charAt(i)=='3')three++;
            }
            hm = new HashMap<>();
            boolean ans = func(num, two, three);
            if(ans)
            System.out.println("YES");
            else System.out.println("NO");
        }
    }
}

Solution 2 (runtime: 249 ms):
import java.io.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.*;
public class main {
    static PrintWriter pw = new PrintWriter(new BufferedOutputStream(System.out));
    static FastReader in = new FastReader();
    public static int n;  
    public static void main(String[] args) {
        int t = in.nextInt();
        while (t-- > 0) {
            String p = in.next();
            n = p.length();
            long sum = 0;
            for (int i = 0; i < n; i++) {
                int l = p.charAt(i) - '0';
                sum += l;
            }
            if (sum % 9 == 0) {
                pw.println("YES");
            } else {
                sum %= 9;
                sum = 9 - sum;

                int count2 = 0;
                int count3 = 0;
                for (int i = 0; i < n; i++) {
                    int l = p.charAt(i) - '0';
                    if (l == 2) {
                        count2++;
                    } else if (l == 3) {
                        count3++;
                    }
                }
                if (sum % 2 != 0) {
                    sum += 9;
                }
                while(count3 > 0 && sum >= 6) {
                    count3--;
                    sum -= 6;
                }
                while(count2 > 0 && sum >= 2) {
                    count2--;
                    sum -= 2;
                }
                if (sum == 0) {
                    pw.println("YES");
                } else {
                    pw.println("NO");
                }
            }
        }
        pw.close();
    }
    
    static class FastReader {
        BufferedReader br;
        StringTokenizer st;

        public FastReader() {
            br = new BufferedReader(new InputStreamReader(System.in));
        }

        String next() {
            while (st == null || !st.hasMoreElements()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

        int nextInt() {
            return Integer.parseInt(next());
        }

        long nextLong() {
            return Long.parseLong(next());
        }

        double nextDouble() {
            return Double.parseDouble(next());
        }

        String nextLine() {
            String str = "";
            try {
                str = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return str;
        }
    }
}