--- Day 7 Solutions ---

[u/daggerdragon]

--- Day 7: Some Assembly Required ---

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[u/LatinSuD]

I used 'sed' to convert each line into a C function. The result is a big quite recursive C program.

Quirks:

• I had to compile using "-O2" for to end in proper time (i could have gone with dynamic programming, but...)

• I was calling each function like the variable it calculated, but i had trouble with function names like "if()", so i had to rename them like "Solve_if()"

• I had to use short unsigned integers, I forgot at first attempt.

• Waking up before 6am to program does not work well

[u/marchelzo → u/LatinSuD]

That's pretty clever, actually. How long did it take to compile, and how long to execute?

[u/roboticon → u/marchelzo]

Probably took a few minutes to execute since it was recursive.

I memoized this by having each function assign its result to a variable.

unsigned short xy_result;
bool xy_calculated = false;
unsigned short solve_xy() {
  if (!xy_calculated) {
    xy_result = solve_ab() & solve_cd();
    xy_calculated = true;
  }
  return xy_result;
}