New update is available. Click here to update.

Solve problems & track your progress

Checkout your overall progress in every topic here

Become

Sensei

in DSA topics

Open the topic and solve more problems associated with it to improve your skills

Check out the skill meter for every topic

See how many problems you are left with to solve for cracking any stage. Score more than zero to get your progress counted.

Problem

Submissions

Best Time to Buy and Sell Stock

Contributed by

Arindam Majumder

Last Updated: 23 Feb, 2023

Medium

0/80

Avg time to solve 20 mins

Success Rate 80 %

212 upvotes

Problem Statement

You are given an array/list 'prices' where the elements of the array represent the prices of the stock as they were yesterday and indices of the array represent minutes. Your task is to find and return the maximum profit you can make by buying and selling the stock. You can buy and sell the stock only once.

Note:

You can’t sell without buying first.

For Example:

For the given array [ 2, 100, 150, 120],
The maximum profit can be achieved by buying the stock at minute 0 when its price is Rs. 2 and selling it at minute 2 when its price is Rs. 150.
So, the output will be 148.

Detailed explanation ( Input/output format, Notes, Images )

Input Format:

The first line contains a single integer ‘T’ denoting the number of test cases to be run. Then the test cases follow.

The first line of each test case contains a single integer ‘N’, representing the size of the array.

The second line of each test case contains ‘N’ space-separated integers representing the elements of the given array.

Output Format:

For each test case, print a single integer representing the maximum profit you can achieve. If the maximum profit is negative, print 0.

Output for each test case will be printed in a separate line.

Note :

You are not required to print anything, it has already been taken care of. Just implement the function.

Constraints:

1 <= T <= 10
2 <= N <= 10^4
1 <= ARR[i] <= 10^9

Time Limit: 1 sec.

Sample Input 1:

Sample Output 1:

3
0

Explanation For Sample Output 1:

For the first test case, it’s optimal to buy the stock at minute 0 and sell it at minute 3 to get a maximum profit of 3.

For the second test case, the maximum profit will be 0 for all possible ways of buying and selling stock.

Sample Input 2:

2
6
17 20 11 9 12 6
4
98 101 66 72

Sample Output 2:

3
6

Autocomplete

Console