254 lines
8.1 KiB
TypeScript
254 lines
8.1 KiB
TypeScript
export type Pos = [number, number];
|
|
export type NumpadRobotState = {
|
|
pos: Pos;
|
|
};
|
|
export type Command = "^" | "v" | "<" | ">" | "A";
|
|
|
|
export function getNextPos(pos: Pos, command: Command): Pos {
|
|
const [x, y] = pos;
|
|
switch (command) {
|
|
case "^":
|
|
return [x, y - 1];
|
|
case "v":
|
|
return [x, y + 1];
|
|
case "<":
|
|
return [x - 1, y];
|
|
case ">":
|
|
return [x + 1, y];
|
|
default:
|
|
return pos;
|
|
}
|
|
}
|
|
|
|
const NumbericKeypad = "789\n456\n123\n 0A";
|
|
export const NUMPAD_FIRST_POS: Pos = [2, 3];
|
|
export function getNumpadNumber([x, y]: Pos): string {
|
|
return NumbericKeypad[y * 4 + x];
|
|
}
|
|
export function getPosFromNumpadNumber(num: string): Pos {
|
|
const idx = NumbericKeypad.indexOf(num);
|
|
return [idx % 4, Math.floor(idx / 4)];
|
|
}
|
|
|
|
export function getNextNumpadRobotState(
|
|
state: NumpadRobotState,
|
|
command: Command,
|
|
): NumpadRobotState {
|
|
const nextPos = getNextPos(state.pos, command);
|
|
const [nx, ny] = nextPos;
|
|
if (
|
|
nx < 0 || nx > 2 || ny < 0 || ny > 3 ||
|
|
getNumpadNumber(nextPos) === " "
|
|
) {
|
|
throw new Error(
|
|
`Invalid command: ${command} for pos: ${state.pos.join(",")} -> ${
|
|
nextPos.join(",")
|
|
} is out of bound`,
|
|
);
|
|
}
|
|
return { pos: nextPos };
|
|
}
|
|
|
|
const DirectionalKeypad = " ^A\n<v>";
|
|
export const DIRPAD_FIRST_POS: Pos = [2, 0];
|
|
export type DirKeypadRobotState = {
|
|
pos: Pos;
|
|
};
|
|
export function getDirpadNumber([x, y]: Pos): string {
|
|
return DirectionalKeypad[y * 4 + x];
|
|
}
|
|
export function getPosFromDirpadNumber(num: string): Pos {
|
|
const idx = DirectionalKeypad.indexOf(num);
|
|
return [idx % 4, Math.floor(idx / 4)];
|
|
}
|
|
|
|
export function getNextDirpadRobotState(
|
|
state: DirKeypadRobotState,
|
|
command: Command,
|
|
): DirKeypadRobotState {
|
|
const nextPos = getNextPos(state.pos, command);
|
|
const [nx, ny] = nextPos;
|
|
if (
|
|
nx < 0 || nx > 2 || ny < 0 || ny > 1 ||
|
|
getDirpadNumber(nextPos) === " "
|
|
) {
|
|
throw new Error(
|
|
`Invalid command: ${command} for pos: ${state.pos.join(",")} -> ${
|
|
nextPos.join(",")
|
|
} is out of bound`,
|
|
);
|
|
}
|
|
return { pos: nextPos };
|
|
}
|
|
|
|
export function executeCommandsOnNumpadRobot(
|
|
state: NumpadRobotState,
|
|
commands: Command[],
|
|
output: (out: string) => void,
|
|
): NumpadRobotState {
|
|
return commands.reduce((state, command) => {
|
|
if (command === "A") {
|
|
output(getNumpadNumber(state.pos));
|
|
}
|
|
return getNextNumpadRobotState(state, command);
|
|
}, state);
|
|
}
|
|
|
|
export function executeCommandsOnDirpadRobot(
|
|
state: DirKeypadRobotState,
|
|
commands: Command[],
|
|
output: (out: string) => void,
|
|
): DirKeypadRobotState {
|
|
return commands.reduce((state, command) => {
|
|
if (command === "A") {
|
|
output(getDirpadNumber(state.pos));
|
|
}
|
|
return getNextDirpadRobotState(state, command);
|
|
}, state);
|
|
}
|
|
|
|
export function shortestPathesOnNumpadRobot(
|
|
state: NumpadRobotState,
|
|
targetNum: string,
|
|
): Command[][] {
|
|
const targetPos = getPosFromNumpadNumber(targetNum);
|
|
const len = Math.abs(targetPos[0] - state.pos[0]) +
|
|
Math.abs(targetPos[1] - state.pos[1]);
|
|
const queue: [Command[], NumpadRobotState][] = [[[], state]];
|
|
const paths: Command[][] = [];
|
|
while (queue.length > 0) {
|
|
const [path, state] = queue.shift()!;
|
|
if (path.length === len) {
|
|
if (
|
|
state.pos[0] === targetPos[0] && state.pos[1] === targetPos[1]
|
|
) {
|
|
paths.push(path);
|
|
}
|
|
continue;
|
|
}
|
|
for (const command of ["^", "v", "<", ">"] as Command[]) {
|
|
try {
|
|
const nextState = getNextNumpadRobotState(state, command);
|
|
queue.push([path.concat(command), nextState]);
|
|
} catch (e) {
|
|
// Ignore invalid command
|
|
}
|
|
}
|
|
}
|
|
return paths;
|
|
}
|
|
|
|
export function shortestPathesOnDirpadRobot(
|
|
state: DirKeypadRobotState,
|
|
targetNum: string,
|
|
): Command[][] {
|
|
const targetPos = getPosFromDirpadNumber(targetNum);
|
|
const len = Math.abs(targetPos[0] - state.pos[0]) +
|
|
Math.abs(targetPos[1] - state.pos[1]);
|
|
const queue: [Command[], DirKeypadRobotState][] = [[[], state]];
|
|
const paths: Command[][] = [];
|
|
while (queue.length > 0) {
|
|
const [path, state] = queue.shift()!;
|
|
if (path.length === len) {
|
|
if (
|
|
state.pos[0] === targetPos[0] && state.pos[1] === targetPos[1]
|
|
) {
|
|
paths.push(path);
|
|
}
|
|
continue;
|
|
}
|
|
for (const command of ["^", "v", "<", ">"] as Command[]) {
|
|
try {
|
|
const nextState = getNextDirpadRobotState(state, command);
|
|
queue.push([path.concat(command), nextState]);
|
|
} catch (e) {
|
|
// Ignore invalid command
|
|
}
|
|
}
|
|
}
|
|
return paths.map((p) => p.concat("A"));
|
|
}
|
|
|
|
export function StepShortestPathesOnDirpadRobot(
|
|
state: DirKeypadRobotState,
|
|
targetNums: string[],
|
|
) {
|
|
return targetNums.reduce( (acc, targetNum) => {
|
|
const prevPos = acc.prevPos;
|
|
const paths = shortestPathesOnDirpadRobot({ pos: prevPos }, targetNum);
|
|
if (paths.length === 0) {
|
|
throw new Error(`No path found for ${targetNum} from ${prevPos}`);
|
|
}
|
|
return {
|
|
prevPos: getPosFromDirpadNumber(targetNum),
|
|
// product of all
|
|
paths: acc.paths.flatMap((p) => paths.map((np) => p.concat(np))),
|
|
}
|
|
}, {
|
|
prevPos: state.pos,
|
|
paths: [[]] as Command[][],
|
|
}).paths;
|
|
}
|
|
|
|
function filterShortestPathes(paths: Command[][]) {
|
|
let len = Number.MAX_SAFE_INTEGER;
|
|
for (const path of paths) {
|
|
len = Math.min(len, path.length);
|
|
}
|
|
// len = Math.min(...paths.map((p) => p.length)); // this is call stack overflow...
|
|
// because the array is too big, the argument list is too long.
|
|
// so we need to calculate the min value by ourself.
|
|
return paths.filter((p) => p.length === len);
|
|
}
|
|
|
|
export function solve_1(code: string) {
|
|
const numbers = code.split("");
|
|
let start = NUMPAD_FIRST_POS;
|
|
|
|
const finalOuts: string[] = [];
|
|
|
|
for (const num of numbers) {
|
|
console.log("num", num);
|
|
const numpadPaths = shortestPathesOnNumpadRobot({ pos: start }, num).map((p) => p.concat("A"));
|
|
if (numpadPaths.length === 0) {
|
|
throw new Error(`No path found for ${num} from ${start}`);
|
|
}
|
|
console.log("avail path", numpadPaths.map((p) => p.join("")));
|
|
const pathes1 = filterShortestPathes(numpadPaths.flatMap((numpadPath) => {
|
|
return StepShortestPathesOnDirpadRobot({ pos: DIRPAD_FIRST_POS }, numpadPath);
|
|
}));
|
|
|
|
console.log("path1",pathes1.map((p) => p.join("")));
|
|
const pathes2 = filterShortestPathes(pathes1.flatMap((path) => {
|
|
return StepShortestPathesOnDirpadRobot({ pos: DIRPAD_FIRST_POS }, path);
|
|
}));
|
|
console.log("path2",pathes2.map((p) => p.join("")));
|
|
const pathes3 = filterShortestPathes(pathes2.flatMap((path) => {
|
|
return StepShortestPathesOnDirpadRobot({ pos: DIRPAD_FIRST_POS }, path);
|
|
}));
|
|
// console.log("path3",pathes3.map((p) => p.join("")));
|
|
const executePath3 = (path: Command[]) => {
|
|
const outs: string[] = [];
|
|
executeCommandsOnDirpadRobot({ pos: DIRPAD_FIRST_POS }, path, (o) => { outs.push(o); });
|
|
console.log("outs", outs.join(""));
|
|
return outs;
|
|
};
|
|
finalOuts.push(...executePath3(pathes3[0]));
|
|
start = getPosFromNumpadNumber(num);
|
|
}
|
|
console.log("finalOuts", finalOuts.join(""), finalOuts.length);
|
|
return finalOuts.length;
|
|
}
|
|
|
|
|
|
if (import.meta.main) {
|
|
const codes = Deno.readTextFileSync("input.txt").replaceAll("\r","").split("\n");
|
|
let total = 0;
|
|
for (const code of codes){
|
|
const len = solve_1(code);
|
|
const n = parseInt(code.slice(0,3));
|
|
console.log("len", len, n, len * n);
|
|
total += n * len;
|
|
}
|
|
console.log("total", total);
|
|
} |