Acpc2014 problem C Solution

scorifyC.java

package problems;

/**
 * @Author Mehdi Maick
 * Created on 30/10/2016.
 */

import java.util.*;
import java.io.*;

import static java.lang.Math.*;

public class scorifyC {

    static long[][] memo;
    static ArrayList<Pair> tab;
    static long S;
    static int n;

    static long f(int i, int sum) {

        if (i < 0)
            return 0L;
        if (memo[i][sum] != -1)
            return memo[i][sum];

        long ans = 0L;

        if (S % (sum + tab.get(i).s) == 0 && tab.get(i).f >= (S / (sum + tab.get(i).s))) {
            ans = 1L;
        }

        ans += f(i - 1, sum);

        if (sum + tab.get(i).s <= S) {

            ans += f(i - 1, sum + tab.get(i).s);
        }
        memo[i][sum] = ans;
        return ans;
    }

    public static void solve(FastReader fs, PrintWriter pw) {

        int t = fs.nextInt();

        for (int ii = 1; ii <= t; ii++) {

            S = fs.nextLong();
            n = fs.nextInt();

            memo = new long[n + 1][(int) S + 1];
            tab = new ArrayList<Pair>();

            for (int i = 0; i < n; i++) {
                tab.add(new Pair(fs.nextInt(), fs.nextInt()));
            }

            for (int i = 0; i <= n; i++) {
                Arrays.fill(memo[i], -1);
            }
            Collections.sort(tab);
            long ans = f(n - 1, 0);
            pw.println("Case " + ii + ": " + ans);
        }
    }

    public static void main(String[] args) throws Exception {
        FastReader fs = new FastReader(System.in);
        PrintWriter pw = new PrintWriter(new OutputStreamWriter(System.out));

        solve(fs, pw);

        fs.close();
        pw.close();
    }

    static class Pair implements Comparable<Pair> {
        int f, s;

        public Pair(int f, int s) {
            this.f = s;
            this.s = f;
        }

        public String toString() {
            return f + " " + s;
        }

        @Override
        public int compareTo(Pair o) {
            if (f == o.f) {
                return s - o.s;
            }
            return f - o.f;
        }
    }

    static class FastReader {

        BufferedReader reader;
        StringTokenizer st;

        FastReader(InputStream stream) {
            reader = new BufferedReader(new InputStreamReader(stream));
            st = null;
        }

        String next() {
            while (st == null || !st.hasMoreTokens()) {
                try {
                    String line = reader.readLine();
                    if (line == null) {
                        return null;
                    }
                    st = new StringTokenizer(line);
                } catch (Exception e) {
                    throw new RuntimeException();
                }
            }
            return st.nextToken();
        }

        String nextLine() {
            String s = null;
            try {
                s = reader.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return s;
        }

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

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

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

        char nextChar() {
            return next().charAt(0);
        }

        int[] nextIntArray(int n) {
            int[] arr = new int[n];
            int i = 0;
            while (i < n) {
                arr[i++] = nextInt();
            }
            return arr;
        }

        long[] nextLongArray(int n) {
            long[] arr = new long[n];
            int i = 0;
            while (i < n) {
                arr[i++] = nextLong();
            }
            return arr;
        }

        int[] nextIntArrayOneBased(int n) {
            int[] arr = new int[n + 1];
            int i = 1;
            while (i <= n) {
                arr[i++] = nextInt();
            }
            return arr;
        }

        long[] nextLongArrayOneBased(int n) {
            long[] arr = new long[n + 1];
            int i = 1;
            while (i <= n) {
                arr[i++] = nextLong();
            }
            return arr;
        }

        void close() {
            try {
                reader.close();
            } catch (IOException e) {
                System.err.println("There's been an error trying closing the reader ");
                e.printStackTrace();
            }
        }
    }


}