1553. Minimum Number of Days to Eat N Oranges

There are n oranges in the kitchen and you decided to eat some of these oranges every day as follows:

• Eat one orange.
• If the number of remaining oranges (n) is divisible by 2 then you can eat n/2 oranges.
• If the number of remaining oranges (n) is divisible by 3 then you can eat 2*(n/3) oranges.

You can only choose one of the actions per day.

Return the minimum number of days to eat n oranges.

Example 1:

Input: n = 10
Output: 4
Explanation: You have 10 oranges.
Day 1: Eat 1 orange,  10 - 1 = 9.
Day 2: Eat 6 oranges, 9 - 2*(9/3) = 9 - 6 = 3. (Since 9 is divisible by 3)
Day 3: Eat 2 oranges, 3 - 2*(3/3) = 3 - 2 = 1.
Day 4: Eat the last orange  1 - 1  = 0.
You need at least 4 days to eat the 10 oranges.

Example 2:

Input: n = 6
Output: 3
Explanation: You have 6 oranges.
Day 1: Eat 3 oranges, 6 - 6/2 = 6 - 3 = 3. (Since 6 is divisible by 2).
Day 2: Eat 2 oranges, 3 - 2*(3/3) = 3 - 2 = 1. (Since 3 is divisible by 3)
Day 3: Eat the last orange  1 - 1  = 0.
You need at least 3 days to eat the 6 oranges.

Example 3:

Input: n = 1
Output: 1

Example 4:

Input: n = 56
Output: 6

Constraints:

• 1 <= n <= 2*10^9

# @lc code=start
using LeetCode

function min_days_1553(n::Int)
    memo = Dict{Int, Int}()
    memo[0] = 0
    memo[1] = 1
    function min_days(n::Int)
        if haskey(memo, n)
            return memo[n]
        end
        return memo[n] = 1 + min(min_days(n ÷ 2) + n % 2, min_days(n ÷ 3) + n % 3)
    end
    min_days(n)
end
# @lc code=end

min_days_1553 (generic function with 1 method)

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