【力扣练习题】121. 买卖股票的最佳时机

class Solution {

public int maxProfit(int[] prices) {

int l = prices.length;

int max = 0;

int minNum = prices[0];

for (int i = 0;i< l;i++) {

minNum = Math.min(prices[i], minNum);

max = Math.max(max, (prices[i] - minNum));

}

return max;

}

}