背包问题贪心算法伪代码
时间: 2023-09-16 11:06:37 浏览: 298
以下是基于贪心算法的背包问题伪代码:
1. 初始化总价值和总重量为0
2. 对于每个物品i,计算其性价比,即价值/重量
3. 按照性价比从大到小排序所有物品
4. 对于每个物品i,如果它的重量小于等于背包剩余容量,则将它装入背包中,并更新总价值和总重量
5. 如果物品i的重量大于背包剩余容量,则将它按照比例拆分,将能够装入的部分装入背包中,并更新总价值和总重量
6. 重复步骤4和5,直到所有物品都被考虑
伪代码如下:
```
function knapsack(weights, values, capacity):
n = length(weights)
ratios = [values[i] / weights[i] for i in range(n)]
sorted_indices = sort_indices(ratios, descending=True)
total_value = 0
total_weight = 0
for i in sorted_indices:
if weights[i] <= capacity:
total_value += values[i]
total_weight += weights[i]
capacity -= weights[i]
else:
fraction = capacity / weights[i]
total_value += fraction * values[i]
total_weight += fraction * weights[i]
break
return total_value, total_weight
```
阅读全文