def knapsack01(weights, values, W):
N = len(weights)
dp = [[0 for _ in range(W + 1)] for _ in range(N + 1)]
for i in range(1, N + 1):
for j in range(1, W + 1):
if j >= weights[i-1]:
dp[i][j] = max(dp[i-1][j], dp[i-1][j-weights[i-1]] + values[i-1])
else:
dp[i][j] = dp[i-1][j]
return dp[N][W]
# 示例
weights = [1, 2, 3]
values = [6, 10, 12]
W = 5
print(knapsack01(weights, values, W))