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Занятие 1. Entering and output of data

Difficulty level:

Task«Black Friday»

You plan to make purchases during Black Friday and want to know the final cost of goods. The user introduces the price of the goods and the percentage of discounts. The program calculates the final cost of goods, taking into account discounts and deduces the integer result. There are always three goods.

Input format

Three lines. Each line contains two integers separated by a gap: first the price of the goods, then the percentage of the discount.

Output format

one line with the text "taking into account the discount, you will spend:" and the final integer amount of all purchases.

Example

Input

5000 15
1000 30
2000 50

Output

Given the discount, you will spend: 5950 руб.

Hint

Reading multiple variables from a single line

Python has a convenient way to count multiple variables in a single input() call. This is especially useful in tasks where data is served in a single line, separated by some character (most often a space).

How it works:

input() reads the entire string, for example "20 30".
The .split() method "cuts" this string by the specified separator (by default, by a space) and creates a list of strings: ['20', '30'].
Function map(int, ...) applies the int (integer conversion) function to each element of this list. The result is a special map object.
Finally, Python "unpacks" this object using the variables a and b.

Example: Input:

20 30

Reading:

a, b = map(int, input().split()) # float can be used if fractional numbers are needed
print(a, b) # outputs 20 30
print(type(a)) # outputs <class 'int'>

Useful tips:

If the numbers are separated not by a space, but, for example, by a comma (input: 20,30), specify this in the split() method: input().split(',').
Make sure that the number of variables to the left of = matches the number of values in the row. If they do not match, the program will return the error ValueError.

Three types of division

There are three different division operators in Python, and each one serves a different purpose.

/ Ordinary (real) division This operator always returns a fractional number (float) as a result, even if the numbers are completely divisible.
```
a = 27
b = 10
print(a/5) # outputs 5.4
print(b/2) # outputs 5.0 (note, not 5, but 5.0)
```
// Integer division This operator performs division and discards the fractional part, returning an integer (int). It sort of answers the question "how many times does one number fit entirely into another?".
```
a = 27
print(a// 5) # outputs 5 (because 5 is placed in 27 five full times)
```

% The remainder of the division (modulo division) This operator returns what is "left" after the integer division.

a = 27
print(a %5) # outputs 2
 Logic: the nearest number to 27 that is divisible by 5 without remainder is 25. 
# Difference: 27-25 = 2.

Practical application %: The most common use of the % operator is the parity check. Any even number is divisible by 2 without remainder, and an odd number is divisible by 1.

a = 27
b = 14
print(f"Is {a} an odd number? The remainder of the division by 2: {a %2}") # outputs 1
print(f"Is {b} an even number? The remainder of the division by 2: {b %2}") # outputs 0

Exponentiation

To exponentiate a number in Python, the ** operator is used.

a = 2
b = 3
print(a**3) # outputs 8 (2 to the power of 3)
print(b**2) # outputs 9(3 to the power of 2)

Useful tips:

To extract the square root, you can raise the number to the power of 0.5.
```
print(9**0.5) # outputs 3.0
```
There is also a built-in function pow(a,b) that does the same thing as a**b.
```
print(pow(2, 3)) # outputs 8
```

print() function and string formatting

The print() function outputs data to the screen. Simply adding strings and variables using + is inconvenient, since numbers need to be constantly converted into strings using str(). Modern Python offers more elegant ways.

f-strings (f-strings) - recommended method: This is the most modern, fastest and most readable way. The string is preceded by the letter f, and variables or expressions are specified inside curly braces {}.

name = "Alice"
age = 30
print(f"Name: {name}, Age: {age}")
# Output: Name: Alice, Age: 30

Advantage: you can perform operations right inside the brackets.

print(f"In a year she will be {age + 1}")
# Conclusion: In a year she will be 31

The .format() method is an older, but still relevant method: Empty curly braces {} are placed in the line, and after the line the .format() method is called, to which variables are passed.

name = "Alice"
age = 30
print("Name: {}, Age: {}".format(name, age))
# Output: Name: Alice, Age: 30

Useful tips for print():

Separator sep: By default, print separates its arguments with a space. This can be changed.
```
print(1, 2, 3, sep="-") # outputs 1-2-3
```
Ending end: By default, print adds a newline after the output \n. This can also be changed so that the following print outputs continue on the same line.
```
print("Hello,", end="")
print("world!")
# The output will be in one line: Hello, world!
```

main.py

Test 1

Test 2

Test 3

Test 4

Test 5

Test 6

Test 7

Developer’s solution

# Считываем данные для первого товара
price1_str, discount1_str = input().split()
price1 = int(price1_str)
discount1 = int(discount1_str)
# Считываем данные для второго товара
price2_str, discount2_str = input().split()
price2 = int(price2_str)
discount2 = int(discount2_str)
# Считываем данные для третьего товара
price3_str, discount3_str = input().split()
price3 = int(price3_str)
discount3 = int(discount3_str)
# Рассчитываем итоговую стоимость каждого товара
final_price1 = price1 * (1 - discount1 / 100)
final_price2 = price2 * (1 - discount2 / 100)
final_price3 = price3 * (1 - discount3 / 100)
# Складываем стоимости и получаем общую сумму
total_cost = final_price1 + final_price2 + final_price3
# Выводим результат, преобразовав его в целое число
print("С учетом скидки вы потратите:", int(total_cost), "руб.")

🎉 Congratulations! 🎉

You did an excellent job with the task! It was a challenging problem, but you found the correct solution. You are one step closer to mastering programming! Keep up the good work, because every stage you pass makes you even stronger.