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Swapnil Gupta
Swapnil Gupta

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Buy and Sell Stocks-I and II

Problem link : https://leetcode.com/problems/best-time-to-buy-and-sell-stock/submissions/
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This is basic array question helps you to understand arrays better

part -1: buying and selling is allowed once

in this we will assume maximum profit zero initially and buying price maximum. We will iterate the array of prices, if we find the minimum buyprice less than the previous buying price we will update the buy price, for this we will use if statement if(prices[i]<buyprice>){ buyprice =price(i);} this loop will execute only if price[i] value is smaller than the buyprice, or we can use the java Math.min class of java.

Similarly, we update the maxProfit if our maxProfit is more than price[i]-buyPrice or previous maxProfit. for this either we can use else if statement or MaxProfit= Math.max(MaxProfit, prices[i]-buyPrice);

class Solution {
    public int maxProfit(int[] prices) {
        int MaxProfit=0;
        int buyPrice= Integer.MAX_VALUE;

        for(int i=0; i< prices.length; i++){
            if(prices[i]<buyPrice){
                buyPrice= prices[i];
            }
         // else if(MaxProfit<prices[i]- buyPrice){
         //    MaxProfit= prices[i]-buyPrice;
            //}
            MaxProfit= Math.max(MaxProfit, prices[i]-buyPrice);


    }
        return MaxProfit;
    }
}
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mariacow profile image
mariacow

I started buying stocks in 2015 when one of my friends started actively investing in real estate and making money from it. Later he became a realtor and opened his own company, while I remained a private broker who helped newcomers choose an investment. I gather all the information for my courses from pennystocks.today and the official social networks of the largest investors in the country. Correctly purchased stocks may not profit right away, so it is important to have patience in investing and wait calmly for the payout from the trade.