Python: Calculate the maximum profit from selling and buying values of stock

Last update on April 17 2025 13:05:34 (UTC/GMT +8 hours)

Max Profit from Stocks

Write a Python program to calculate the maximum profit from selling and buying values of stock. An array of numbers represent the stock prices in chronological order.
For example, given [8, 10, 7, 5, 7, 15], the function will return 10, since the buying value of the stock is 5 dollars and sell value is 15 dollars.

Sample Solution:

Python Code:

# Define a function to calculate the maximum profit from buying and selling stocks
def buy_and_sell(stock_price):
    # Initialize variables to store the maximum profit and current maximum value
    max_profit_val, current_max_val = 0, 0
    
    # Iterate through the reversed stock prices
    for price in reversed(stock_price):
        # Update the current maximum value with the maximum of the current value and the previous maximum
        current_max_val = max(current_max_val, price)
        
        # Calculate the potential profit by subtracting the current price from the current maximum value
        potential_profit = current_max_val - price
        
        # Update the maximum profit with the maximum of the potential profit and the previous maximum profit
        max_profit_val = max(potential_profit, max_profit_val)

    # Return the maximum profit
    return max_profit_val

# Test the function with different stock price lists and print the results
print(buy_and_sell([8, 10, 7, 5, 7, 15]))  # Maximum Profit: 10
print(buy_and_sell([1, 2, 8, 1]))           # Maximum Profit: 7
print(buy_and_sell([]))                      # Maximum Profit: 0

Sample Output:

10
7
0

Explanation:

Here is a breakdown of the above Python code:

The function "buy_and_sell()" calculates the maximum profit from buying and selling stocks.
It iterates through the reversed 'stock_price' list, starting from the end.
For each price, it updates the 'current_max_val' with the maximum of the current value and the previous maximum.
It calculates the potential profit by subtracting the current price from the 'current_max_val'.
It updates the 'max_profit_val' with the maximum of the potential profit and the previous maximum profit.
The function returns the final maximum profit value.
Test the function with different stock price lists and print the results.

Flowchart:

For more Practice: Solve these Related Problems:

Write a Python program to calculate the maximum profit from stock prices with a single buy and sell transaction.
Write a Python program to determine the best days to buy and sell stock to achieve the maximum profit using a one-pass algorithm.
Write a Python program to compute the optimal profit by tracking the minimum price and calculating potential gains at each step.
Write a Python program to find the maximum profit from a series of stock prices by iterating through the price list only once.

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Next: Write a Python program to remove all instances of a given value from a given array of integers and find the length of the new array.

Python Code Editor:

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