핸드헬드 정지

코드 출현 2020 8일차

과제: X에 대해 풀기 여기서...

X = the value of accumulator at some N time

예시 입력

nop +0
acc +1
jmp +4
acc +3
jmp -3
acc -99
acc +1
jmp -4
acc +6

1 부

추적할 항목 식별

작동할 것으로 생각되는 알고리즘 작성

Split the input at each new line character into an array of strings
Split each string at the space character into a 2-element array of strings
Convert the second string into a positive or negative number

Set an accumulator at 0
Set a unique list of indices as empty
Set the next instruction line index as 0

Do as long as the next instruction line index is not in the unique list of indices
  Look-up the 2-item array at the next index
  If the first item is 'nop'
    Add the index to the unique list
    Increment the value stored in next instruction line
  Else, if the first item is 'acc'
    Add to accumulator the value stored in the second item
    Add the index to the unique list
    Increment the value stored in next instruction line
  Else, if the first item is 'jmp'
    Add the index to the unique list
    Update the value stored in next instruction line to the sum of this item's index and the value of the second element

The above loop should finish as soon as the next instruction line's index is the first to already be in the unique set, meaning it has been visited

Return accumulator

효과가 있어서 웃는다

2 부

내 무차별 대입 작업 알고리즘

Set a correct accumulator that will eventually reflect the fully accumulated value from the program that runs to termination

Identify each instruction line with either a `nop` or `jmp` operation

For each of those lines
  Create a clone of the full list of instructions
  Change the operation at the current line to swap 'nop' for 'jmp' or vice versa
  Run the single-line modified program, tracking the unique set of indices visited, the next index expected, and an accumulator...until the next index exists in the unique set of indices visited

  As soon as the next index expected is equivalent to the length of the list of instructions - indicating that the program finally terminated:
    Update the correct accumulator to equal the currently tracked local accumulator
    Break out of the outer loop

Return the newly-set value in the correct accumulator

내 알고리즘의 성능을 고려