Python基于动态规划算法解决01背包问题实例

def bag(n,c,w,v):
  res=[[-1 for j in range(c+1)] for i in range(n+1)]
  for j in range(c+1):
    res[0][j]=0
  for i in range(1,n+1):
    for j in range(1,c+1):
      res[i][j]=res[i-1][j]
      if j>=w[i-1] and res[i][j]<res[i-1][j-w[i-1]]+v[i-1]:
        res[i][j]=res[i-1][j-w[i-1]]+v[i-1]
  return res
def show(n,c,w,res):
  print('最大价值为:',res[n][c])
  x=[False for i in range(n)]
  j=c
  for i in range(1,n+1):
    if res[i][j]>res[i-1][j]:
      x[i-1]=True
      j-=w[i-1]
  print('选择的物品为:')
  for i in range(n):
    if x[i]:
      print('第',i,'个,',end='')
  print('')
if __name__=='__main__':
  n=5
  c=10
  w=[2,2,6,5,4]
  v=[6,3,5,4,6]
  res=bag(n,c,w,v)
  show(n,c,w,res)