/**
 * @param {number[]} prices
 * @return {number}
 */
var maxProfit = function (prices) {
  let ans = [];
  for (let i = 0; i < prices.length - 1; i++) {
    let max = prices[i + 1];
    for (let j = i + 2; j < prices.length; j++) {
      if (max < prices[j]) max = prices[j];
    }
    ans.push(max - prices[i]);
  }
  const ret = Math.max(...ans);
  return ret < 0 ? -1 : ret;
};

console.log(maxProfit([7, 6, 4, 3, 1]));

/**
 * @param {number[]} prices
 * @return {number}
 */
var maxProfit = function (prices) {
  let result = 0;
  let min = prices[0];
  for (let i = 1; i < prices.length; i++) {
    min = Math.min(min, prices[i]);
    result = Math.max(result, prices[i] - min);
  }
  return result;
};

console.log(maxProfit([7, 1, 5, 3, 6, 4]));