Submission #762877

#	Time	Username	Problem	Language	Result	Execution time	Memory
762877		Oz121	Knapsack (NOI18_knapsack)	Java	0 / 100	90 ms	10152 KiB

knapsack

import java.io.*;
import java.util.*;
public class knapsack {
    public static void main(String[] args) throws IOException {
        BufferedReader scan = new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer l1 = new StringTokenizer(scan.readLine());
        int W = Integer.parseInt(l1.nextToken()); int num = Integer.parseInt(l1.nextToken());

        int[][] arr = new int[num][3];
        for (int i = 0;i<num;i++) {
            StringTokenizer st = new StringTokenizer(scan.readLine());
            arr[i][0] = Integer.parseInt(st.nextToken());
            arr[i][1] = Integer.parseInt(st.nextToken());
            arr[i][2] = Integer.parseInt(st.nextToken());
        }
        Arrays.sort(arr,(a,b)->a[1]==b[1] ? b[0]-a[0] : a[1]-b[1]);
        printMat(arr);

        //Arrange by the weight.

        ArrayList<Pair> weights = new ArrayList<>();

        int idx = 0;
        for (int i = 1;i<W+1;i++) {
            ArrayList<Pair> temp = new ArrayList<>();

            while (idx<num&&arr[idx][1]==i) {
                int max = (int) Math.floor((double) W/i);

                if (temp.size()<max) {
                    for (int j = 0;j<arr[idx][2]&&temp.size()<max;j++)
                        temp.add(new Pair (arr[idx][1],arr[idx][0]));
                }
                idx++;
            }

            for (int j = 0;j<temp.size();j++) {
                weights.add(temp.get(j));
            }
        }

        //System.out.println(weights);

        int size = weights.size();
        int[][] dp = new int[size][W+1];
        dp[0][weights.get(0).weight] = weights.get(0).val;

        for (int i = 1;i<size;i++) {
            for (int j = 0;j<=W;j++) {
                dp[i][j] = dp[i-1][j];

                if (j-weights.get(i).weight>=0) {
                    dp[i][j] = Math.max(dp[i][j],dp[i-1][j-weights.get(i).weight]+weights.get(i).val);
                }
            }
        }

        int ans = -1;
        for (int j = 0;j<=W;j++) {
            ans = Math.max(ans,dp[size-1][j]);
        }
        System.out.println(ans);
    }

    public static class Pair {
        int weight; int val;

        Pair (int weight, int val){
            this.weight = weight;
            this.val = val;
        }

        @Override
        public String toString() {
            return weight+" "+val;
        }
    }

    public static void printMat (int[][] arr) {
        for (int i = 0;i<arr.length;i++) {
            for (int j = 0;j<arr[0].length;j++) {
                System.out.print(arr[i][j]+" ");
            }
            System.out.println();
        }
    }
}

• Subtask 1: 0 / 12
• Subtask 2: 0 / 17
• Subtask 3: 0 / 20
• Subtask 4: 0 / 24
• Subtask 5: 0 / 27