2511-maximum-enemy-forts-that-can-be-captured.js

/**
 * 2511. Maximum Enemy Forts That Can Be Captured
 * https://leetcode.com/problems/maximum-enemy-forts-that-can-be-captured/
 * Difficulty: Easy
 *
 * You are given a 0-indexed integer array forts of length n representing the positions of
 * several forts. forts[i] can be -1, 0, or 1 where:
 * - -1 represents there is no fort at the ith position.
 * - 0 indicates there is an enemy fort at the ith position.
 * - 1 indicates the fort at the ith the position is under your command.
 *
 * Now you have decided to move your army from one of your forts at position i to an empty
 * position j such that:
 * - 0 <= i, j <= n - 1
 * - The army travels over enemy forts only. Formally, for all k where min(i,j) < k < max(i,j),
 *   forts[k] == 0.
 *
 * While moving the army, all the enemy forts that come in the way are captured.
 *
 * Return the maximum number of enemy forts that can be captured. In case it is impossible to
 * move your army, or you do not have any fort under your command, return 0.
 */

/**
 * @param {number[]} forts
 * @return {number}
 */
var captureForts = function(forts) {
  let result = 0;
  let start = -1;

  for (let i = 0; i < forts.length; i++) {
    if (forts[i] === 1 || forts[i] === -1) {
      if (start !== -1 && forts[start] !== forts[i]) {
        result = Math.max(result, i - start - 1);
      }
      start = i;
    }
  }

  return result;
};