Buy And Sell Stocks - Infinite Transactions Allowed

 1. You are given a number n, representing the number of days.

2. You are given n numbers, where ith number represents price of stock on ith day.

3. You are required to print the maximum profit you can make if you are allowed infinite transactions.

Note: There can be no overlapping transaction. One transaction needs to be closed (a buy followed by a sell) before opening another transaction (another buy)

Input Format

A number n

.. n more elements

Output Format

A number representing the maximum profit you can make if you are allowed infinite transactions.

Constraints

0 <= n <= 20

0 <= n1, n2, .. <= 10

Sample Input

9

11

6

7

19

4

1

6

18

4

Sample Output

30

Solution: 

import java.io.*;

import java.util.*;

public class Main {

    public static void main(String[] args) throws Exception {

        // write your code here

        Scanner sc = new Scanner(System.in);

        int n = sc.nextInt();

        int[] A = new int[n];

        for(int i=0;i<n;i++)

            A[i] = sc.nextInt();

       

        int profit = 0, msf = A[0];

        for(int i=1;i<n;i++){

            if(A[i]>msf){

                profit += A[i] - msf;

            }

            msf = A[i];

        }

        System.out.println(profit);

    }

}