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/**
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 * @param {number[]} commands
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 * @param {number[][]} obstacles
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 * @return {number}
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 */
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var robotSim = function (commands, obstacles) {
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  let result = 0;
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  let currentPosition = [0, 0];
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  let currentDirection = "top";
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  const mySet = new Set();
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  // This is to have a O(1) check instead of doing a linear scan
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  obstacles.forEach((obs) => {
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    mySet.add(`${obs[0]},${obs[1]}`);
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  }); // O(m)
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  for (let i = 0; i < commands.length; i++) {
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    // O(n)
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    const move = commands[i];
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    if (move === -1) {
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      if (currentDirection === "top") {
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        currentDirection = "right";
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      } else if (currentDirection === "right") {
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        currentDirection = "down";
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      } else if (currentDirection === "down") {
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        currentDirection = "left";
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      } else {
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        currentDirection = "top";
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      }
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    }
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    if (move === -2) {
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      if (currentDirection === "top") {
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        currentDirection = "left";
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      } else if (currentDirection === "left") {
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        currentDirection = "down";
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      } else if (currentDirection === "down") {
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        currentDirection = "right";
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      } else {
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        currentDirection = "top";
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      }
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    }
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    if (move > 0) {
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      for (let i = 0; i < move; i++) {
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        O(move);
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        const isY = currentDirection === "top" || currentDirection === "down";
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        const isPositive =
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          currentDirection === "top" || currentDirection === "right";
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        const newPosition = [
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          currentPosition[0] + (!isY ? (isPositive ? 1 : -1) : 0),
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          currentPosition[1] + (isY ? (isPositive ? 1 : -1) : 0),
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        ];
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        const positionString = `${newPosition[0]},${newPosition[1]}`;
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        if (!mySet.has(positionString)) {
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          currentPosition = newPosition;
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          result = Math.max(
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            result,
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            Math.pow(currentPosition[0], 2) + Math.pow(currentPosition[1], 2)
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          );
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        } else {
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          break;
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        }
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      }
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    }
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  }
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  return result;
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};