45 lines
1.2 KiB
JavaScript
45 lines
1.2 KiB
JavaScript
|
const DEPTH = 7;
|
||
|
|
|
||
|
|
const DIRECTION = {
|
||
|
|
0: new cx(0, 1),
|
||
|
|
1: new cx(0, -1),
|
||
|
|
};
|
||
|
|
|
||
|
|
const move = (prev, curr, c) => cx.add(prev, cx.mult(c, cx.sub(curr, prev)));
|
||
|
|
const construct_moves = (curr, prev) =>
|
||
|
|
Object.keys(DIRECTION).map((x) => move(curr, prev, DIRECTION[x]));
|
||
|
|
const backtrack = (local_index, depth) =>
|
||
|
|
local_index
|
||
|
|
.toString(2)
|
||
|
|
.padStart(depth, "0")
|
||
|
|
.split("")
|
||
|
|
.reverse()
|
||
|
|
.map((dir) => (dir ? "+" : "-"));
|
||
|
|
|
||
|
|
const sol = (target, start_from = new cx(0, 0), start_to = new cx(1, 0)) => {
|
||
|
|
let moves = construct_moves(start_from, start_to);
|
||
|
|
let curr_depth = 2; // potential bug: when target is within one move away
|
||
|
|
|
||
|
|
do {
|
||
|
|
for (let i = 0; i < Math.pow(2, curr_depth); i++) {
|
||
|
|
const current_i =
|
||
|
|
(i >> 1) + ((1 - Math.pow(2, curr_depth - 1)) / (1 - 2) - 1);
|
||
|
|
const previous_i =
|
||
|
|
(i >> 2) + ((1 - Math.pow(2, curr_depth - 2)) / (1 - 2) - 1);
|
||
|
|
|
||
|
|
const new_move = move(
|
||
|
|
previous_i < 0 ? start_from : moves[previous_i],
|
||
|
|
moves[current_i],
|
||
|
|
DIRECTION[parseInt(i.toString(2)[0])]
|
||
|
|
);
|
||
|
|
|
||
|
|
if (cx.eq(new_move, target)) return backtrack(moves, target);
|
||
|
|
|
||
|
|
moves.push(new_move);
|
||
|
|
}
|
||
|
|
curr_depth++;
|
||
|
|
} while (curr_depth < DEPTH);
|
||
|
|
console.log(moves);
|
||
|
|
return null;
|
||
|
|
};
|