[LeetCode] 121. Best Time to Buy and Sell Stock

    

＂踏上LeetCode解題之路，順手紀錄一下PHP練功的過程囉。這是第十二篇~~＂

Best Time to Buy and Sell Stock - LeetCode

思考過程

待補上

結果✅

// 相減 找出利潤最大值

class Solution {

    /**
     * @param Integer[] $prices
     * @return Integer
     */
   function maxProfit(array $prices) {
       
        $min= $prices[0];
        $maxProfit = 0;
       
        for ($i = 1; $i < count($prices); $i++) {
            if ($min > $prices[$i]) {
                $min = $prices[$i];
            }

            if ($maxProfit < ($prices[$i] - $min)) {
                $maxProfit = $prices[$i] - $min;
            }
        }
        return $maxProfit;
    
    
}

/**
 * @param  array $prices Stock prices array for each day.
 * @return int   the max profit possible in the market.
 */
function maxProfit(array $prices) {
  $maxProfit = 0;
  
  for ($i = 0; $i < count($prices); $i++) {
    for($j = $i +1; $j < count($prices); $j++) {
      if ($prices[$i] >= $prices[$j]) {
        continue;
      }
      
      $diff = $prices[$j] - $prices[$i];
      $maxProfit = $diff > $maxProfit ? $diff : $maxProfit;
    }
  }
  
  return $maxProfit;
}

    if ($buy > $maxProfit){
                 $maxProfit = $buy;
            }