#3189 - Minimum Moves to Get a Peaceful Board

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Problem Description

Given a 2D array rooks of length n, where rooks[i] = [xi, yi] indicates the position of a rook on an n x n chess board. Your task is to move the rooks 1 cell at a time vertically or horizontally (to an adjacent cell) such that the board becomes peaceful.

A board is peaceful if there is exactly one rook in each row and each column.

Return the minimum number of moves required to get a peaceful board.

Note that at no point can there be two rooks in the same cell.

Solution

/**
 * @param {number[][]} rooks
 * @return {number}
 */
var minMoves = function(rooks) {
  const rows = rooks.map(rook => rook[0]).sort((a, b) => a - b);
  const cols = rooks.map(rook => rook[1]).sort((a, b) => a - b);

  let result = 0;
  for (let i = 0; i < rooks.length; i++) {
    result += Math.abs(rows[i] - i) + Math.abs(cols[i] - i);
  }

  return result;
};