@@ -339,38 +339,63 @@ public class BagProblem {
339339```
340340
341341### python
342+ 无参数版
343+ ``` python
344+ def test_2_wei_bag_problem1 ():
345+ weight = [1 , 3 , 4 ]
346+ value = [15 , 20 , 30 ]
347+ bagweight = 4
348+ 349+ # 二维数组
350+ dp = [[0 ] * (bagweight + 1 ) for _ in range (len (weight))]
351+ 352+ # 初始化
353+ for j in range (weight[0 ], bagweight + 1 ):
354+ dp[0 ][j] = value[0 ]
355+ 356+ # weight数组的大小就是物品个数
357+ for i in range (1 , len (weight)): # 遍历物品
358+ for j in range (bagweight + 1 ): # 遍历背包容量
359+ if j < weight[i]:
360+ dp[i][j] = dp[i - 1 ][j]
361+ else :
362+ dp[i][j] = max (dp[i - 1 ][j], dp[i - 1 ][j - weight[i]] + value[i])
342363
364+ print (dp[len (weight) - 1 ][bagweight])
365+ 366+ test_2_wei_bag_problem1()
367+ 368+ ```
369+ 有参数版
343370``` python
344- def test_2_wei_bag_problem1 (bag_size , weight , value ) -> int :
345- rows, cols = len (weight), bag_size + 1
346- dp = [[0 for _ in range (cols)] for _ in range (rows)]
347- 348- # 初始化dp数组.
349- for i in range (rows):
350- dp[i][0 ] = 0
351- first_item_weight, first_item_value = weight[0 ], value[0 ]
352- for j in range (1 , cols):
353- if first_item_weight <= j:
354- dp[0 ][j] = first_item_value
355- 356- # 更新dp数组: 先遍历物品, 再遍历背包.
357- for i in range (1 , len (weight)):
358- cur_weight, cur_val = weight[i], value[i]
359- for j in range (1 , cols):
360- if cur_weight > j: # 说明背包装不下当前物品.
361- dp[i][j] = dp[i - 1 ][j] # 所以不装当前物品.
362- else :
363- # 定义dp数组: dp[i][j] 前i个物品里,放进容量为j的背包,价值总和最大是多少。
364- dp[i][j] = max (dp[i - 1 ][j], dp[i - 1 ][j - cur_weight]+ cur_val)
365- 366- print (dp)
371+ def test_2_wei_bag_problem1 (weight , value , bagweight ):
372+ # 二维数组
373+ dp = [[0 ] * (bagweight + 1 ) for _ in range (len (weight))]
367374
375+ # 初始化
376+ for j in range (weight[0 ], bagweight + 1 ):
377+ dp[0 ][j] = value[0 ]
378+ 379+ # weight数组的大小就是物品个数
380+ for i in range (1 , len (weight)): # 遍历物品
381+ for j in range (bagweight + 1 ): # 遍历背包容量
382+ if j < weight[i]:
383+ dp[i][j] = dp[i - 1 ][j]
384+ else :
385+ dp[i][j] = max (dp[i - 1 ][j], dp[i - 1 ][j - weight[i]] + value[i])
386+ 387+ return dp[len (weight) - 1 ][bagweight]
368388
369389if __name__ == " __main__"
370- bag_size = 4
371- weight = [1 , 3 , 4 ]
372- value = [15 , 20 , 30 ]
373- test_2_wei_bag_problem1(bag_size, weight, value)
390+ 391+ weight = [1 , 3 , 4 ]
392+ value = [15 , 20 , 30 ]
393+ bagweight = 4
394+ 395+ result = test_2_wei_bag_problem1(weight, value, bagweight)
396+ print (result)
397+ 398+ 374399```
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