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多个背包问题--邻域算法

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多个背包问题--邻域算法

import sys
import numpy as np

def greedy(p,weight,W):
    count_weight = 0
    count_p = 0
    value = []
    bag_list_p = []
    bag_list_weight=[]
    for i in range(len(p)):
        t = p[i]/weight[i]
        value.append(t)

    for i in range(len(W)):
        bag_list_p.append([])
        bag_list_weight.append([])

    for i in range(len(W)):
        temp_p=p[:]
        temp_weight=weight[:]
        temp_value=value[:]
        for j in range(len(p)):
            x = np.array(temp_value)
            y = x.argsort()
            maxvalue=y[-1]
            if temp_weight[maxvalue]<=W[i]:
                W[i]=W[i]-temp_weight[maxvalue]
                count_weight=count_weight+temp_weight[maxvalue]
                count_p = count_p + temp_p[maxvalue]
                bag_list_p[i].append(temp_p[maxvalue])
                bag_list_weight[i].append(temp_weight[maxvalue])
                p.pop(maxvalue)
                weight.pop(maxvalue)
                value.pop(maxvalue)
                temp_p = p[:]
                temp_weight = weight[:]
                temp_value = value[:]
            else:
                temp_p.pop(maxvalue)
                temp_weight.pop(maxvalue)
                temp_value.pop(maxvalue)
    return bag_list_p,bag_list_weight,p,weight,W,count_p


def NeighborhoodSearch(p,weight,W):
    bag_list_p, bag_list_weight, p, weight ,W,count_p= greedy(p, weight, W)
    change=0
    for i in range(len(W)-1):
        for j in range(i+1,len(W)):
            for m in range(len(bag_list_p[i])):
                for n in range(len(bag_list_p[j])):
                    if(bag_list_weight[i][m]bag_list_p[j][n]):
                            change=1
                            count_p=count_p+new_count_p
                            print("Find a better value: ",count_p)
                            x=bag_list_p[j][n]
                            y=bag_list_weight[j][n]
                            bag_list_p[j].pop(n)
                            bag_list_weight[j].pop(n)
                            bag_list_p[j].append(bag_list_p[i][m])
                            bag_list_weight[j].append(bag_list_weight[i][m])
                            bag_list_p[i].pop(m)
                            bag_list_weight[i].pop(m)
                            for q in range(len(W)):
                                for p in range(len(new_bag_list_weight[q])):
                                    bag_list_p[q].append(new_bag_list_p[q][p])
                                    bag_list_weight[q].append(new_bag_list_weight[q][p])
                            p=new_p
                            weight=new_weight
                            p.append(x)
                            weight.append(y)
                            W=new_W[:]
                        else:
                            count_p=count_p+bag_list_p[j][n]
                            W[i] = W[i] - bag_list_weight[i][m]
                            W[j] = W[j] + bag_list_weight[i][m] - bag_list_weight[j][n]
    if(change==0):
        print("No better value was found")

#sys.exit()

#test case 0: 14,没更好的
weight_0=[1,2,3,4,5,6]
value_0= [2,3,4,5,6,7]
knapsacks_0=[12]

#test case 1:14,没更好的
weight_1=[4,5,6,7,1,3]
value_1= [3,4,5,5,2,3]
knapsacks_1=[10,2,5,6,3,2]

#test case 2:6,没更好的
weight_2=[1,1,1,1,1,1]
value_2= [1,1,1,1,1,1]
knapsacks_2=[10,2,1,3]

#test case 3:20,没更好的
weight_3=[1,2,3,4,5,6]
value_3= [2,3,4,5,6,7]
knapsacks_3=[10,2,6,3]

"""#test case 4:42->44
weight_4=[1,2,3,4,5,6,1,1,5,6,7,1,3,1,1,2,3,2,1,4]
value_4= [2,3,4,5,6,7,1,1,4,5,5,2,3,1,2,3,4,4,4,9]
knapsacks_4=[10,2,5,6,3,2]"""

#test case 5
weight_5=[35,30,60,50,40,
          10,25,54,26,75,
          24,75,78,33,16,
          65,26,56,89,58]
value_5= [10,40,30,50,35,
          40,30,31,22,17,
          22,56,85,33,64,
          86,80,57,38,45]
knapsacks_5=[165,184,148]

w = [3,4,4,3,4,5,3,6,7,3,4,5,5,5,6]
v = [5,6,6,3,4,5,3,6,6,1,2,3,4,3,3]
p = [8,9,10,11,12]
"""Find a better value:  47
Find a better value:  48
Find a better value:  49
Find a better value:  51"""

#test case 4:
weight_4=[1,2,3,4,5,6,5,6,7,1]
value_4= [2,3,4,5,6,7,4,5,5,2]
knapsacks_4=[10,5,8]
#NeighborhoodSearch(v,w,p)
#NeighborhoodSearch(value_5,weight_5,knapsacks_5)
#NeighborhoodSearch(value_0,weight_0,knapsacks_0)
NeighborhoodSearch(value_4,weight_4,knapsacks_4)
#NeighborhoodSearch(value_1,weight_1,knapsacks_1)
#NeighborhoodSearch(value_2,weight_2,knapsacks_2)
#NeighborhoodSearch(value_3,weight_3,knapsacks_3)

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