# Wolf of Wall Street 2 - 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 once.

You must buy before you can sell it.

Note: You are not required to buy or sell the stock.

Constraints

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

Example 1

Input
prices = [9, 11, 8, 5, 7, 10]

Output
5

Explanation
You can buy at 5 and sell at 10.

Example 2

Input
prices = [1, 2, 3, 4, 5, 6, 7, 8, 9]

Output
8

Explanation
You can buy at 1 and sell at 9.

Example 3

Input
prices = [9, 8, 7, 6, 5, 4, 3, 2, 1]

Output
0

Explanation
The stock's only going down so we don't buy at all.```

### Solution :

```                        ```Solution in C++ :

int solve(vector<int>& prices) {
int profit = 0;
int low = INT_MAX;

for (auto x : prices) {
low = min(low, x);

profit = max(profit, x - low);
}
return profit;
}```
```

```                        ```Solution in Java :

import java.util.*;

class Solution {
public int solve(int[] prices) {
int len = prices.length;
if (len == 0 || len == 1)
return 0;
int min = prices[0], diff = 0;
for (int i = 1; i < len; i++) {
if (prices[i] - min > diff) {
diff = prices[i] - min;
}
if (prices[i] < min) {
min = prices[i];
}
}
return diff;
}
}```
```

```                        ```Solution in Python :

class Solution:
def solve(self, prices):
if len(prices) < 2:
return 0
maxProfit = 0
min = prices[0]
for i in prices[1:]:
if i - min > maxProfit:
maxProfit = i - min
if i < min:
min = i
return maxProfit```
```

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