Wolves of Wall Street - Amazon Top Interview Questions

Problem Statement :

Given a list of integers prices representing the stock prices of a company in chronological order, return the maximum profit you could have made from buying and selling that stock any number of times.

You must buy before you can sell it. But you are not required to buy or sell the stock.


0 ≤ n ≤ 100,000 where n is the length of prices

Example 1


prices = [1, 5, 3, 4, 6]



We can buy at 1, sell at 5, buy at 3, and sell at 6.

Solution :


                        Solution in C++ :

int solve(vector<int>& prices) {
    int profit = 0;
    for(int i=0; i<prices.size(); i++){
        int buy = prices[i];
        while(prices[i] <= prices[i+1] && i+1 < prices.size())
        profit += prices[i] - buy;
    return profit; 

                        Solution in Java :

import java.util.*;

class Solution {
    public int solve(int[] prices) {
        int diff = 0;
        for (int i = 0; i < prices.length - 1; i++) {
            if (prices[i] < prices[i + 1])
                diff = diff + prices[i + 1] - prices[i];
        return diff;

                        Solution in Python : 
class Solution:
    def solve(self, prices):
        prev_price, profit = float("inf"), 0
        for p in prices:
            if p > prev_price:
                profit += p - prev_price
            prev_price = p
        return profit

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