背包问题V2

题目链接：51Nod 1086

import java.util.Scanner;

public class Main {

    static int[] c;
    static int[] v;
    static int[] a;
    static int[] f;
    static int N;
    static int V;
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        N = scanner.nextInt();
        V = scanner.nextInt();
        c = new int[105];
        v = new int[105];
        a = new int[105];
        for(int i = 0; i < N; i++) {
            c[i] = scanner.nextInt();
            v[i] = scanner.nextInt();
            a[i] = scanner.nextInt();
        }

        f = new int[V+1];

        for(int i = 0; i < N; i++) {
            multiplePack(c[i], v[i], a[i]);
        }
        System.out.println(f[V]);
    }
    public static void multiplePack(int cost,int weight,int amount) {
        if(cost * amount >= V) {
            completePack(cost, weight);
            return;
        }
        int k = 1;
        while(k < amount) {
            zeroOnePack(k * cost, k * weight);
            amount -= k;
            k *= 2;
        }
        zeroOnePack(amount * cost, amount * weight);
    }

    public static void completePack(int cost,int weight) {
            for(int j = cost; j <= V; j++) {
                f[j] = Math.max(f[j], f[j-cost] + weight);
        }
    }

    public static void zeroOnePack(int cost,int weight) {
            for(int j = V; j >= cost; j--) {
                f[j] = Math.max(f[j], f[j-cost] + weight);
        }
    }
}