Knapsack (0/1 and unbounded)

Learn Algorithms · 3:02

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Lyrics

[Verse 1]
Got a knapsack problem on my mind today
Items with their weights and values in the way
Zero-one means each item just once or never
Dynamic programming makes the solver clever
Build a table row by row, decision by decision
Include or exclude with mathematical precision
Weight capacity sets the boundary line
Maximum value is what we're trying to find

[Chorus]
Knapsack zero-one, take it or leave it
Dynamic table helps you to achieve it
Row by row, column by column we go
Max of include or exclude, let the values flow
Unbounded means unlimited supply
Take as many as the weight allows you to try
Same item over and over again
Till the knapsack reaches capacity's end

[Verse 2]
Zero-one knapsack, each item's unique
Previous row tells you what results to seek
If weight's too heavy, take the value above
Otherwise compare, choose the one you love
Take the item plus remaining space value
Or skip the item, previous row's rescue
Whichever gives you more, that's your choice
Let the maximum value be your guide's voice

[Chorus]
Knapsack zero-one, take it or leave it
Dynamic table helps you to achieve it
Row by row, column by column we go
Max of include or exclude, let the values flow
Unbounded means unlimited supply
Take as many as the weight allows you to try
Same item over and over again
Till the knapsack reaches capacity's end

[Bridge]
Time complexity's order n times w
Space can be optimized to just one-d view
Unbounded's simpler, just one dimension needed
Current row references, efficiency succeeded
Coin change problems use this pattern too
Unlimited denominations working through

[Verse 3]
Unbounded knapsack breaks the single rule
Multiple copies make it a different tool
For each position check every item's worth
Add its value to remaining space's girth
No previous row needed in this game
Current row updates, result's the same
Each cell depends on cells to the left
Maximum value, that's the final gift

[Outro]
From zero-one constraint to unlimited flow
Dynamic programming solutions help us grow
Knapsack problems everywhere you see
Optimization's the master key

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