from math import pi

def volume(r):
    v = ((4*pi*r**3)/3)
    return v

print(volume(2))

Program Explanation:

• We have in-built module math which carries most of the math functions required for mathematical calculations.
• We used ‘pi’ function here
• which is already defined in the math module of python. i.e. (pi = 3.14).
• Hence we have passed the value of radius to calculate the volume of a sphere.

n = int(input("Enter number: "))
for i in range(n):
    for j in range(i):
        print(i, end=" ")
    print("\n")

Program Explanation:

• Here in this program, we have used two for loops with range functions.
• The iteration of the first for loop depends upon the input provided by the user.
• The iteration of the second for loop depends upon the first loop.
• Second for loop printing the value of i in the same line. i.e. end=” ” is same
• In the next line, we are using the ‘\n’ approach for next line.

for i in range(1,30):
    if i%7 == 0:
        print(i, end=" ")

Program Explanation:

• The modulus operator (%) returns the remainder after division of two operands.
• So, ‘i%7 == 0’ it only returns True if condition satisfies.
• If the condition gets false it will not enter to if condition.
• Hence it only returns the True value divisible by 7.

a = int(input("Enter value of a: "))
b = int(input("Enter value of b: "))
print(f"\na is {a} b is {b}")
a = a + b
b = a - b
a = a - b
print("\nafter swapping")
print(f"a is {a} b is {b}")

Program Explanation:

• Here we have used some logic and opearators to achieve our goal.

val = input("Enter any character: ")
if val in ['a','e','i','o','u']:
    print(f"{val} is vowel")
else:
    print(f"{val} is consonent")

Program Explanation:

• Here we used the membership operator ‘in’ to check whether the value exists in the list or not.
• If exist i.e if the entered value by user is exist in the list then It returns true and enters to the if condition and prints value is a vowel.
• Else if the entered value entered by user does not exist in the list then it enters the else condition and returns value is consonant.

a = int(input("Enter value of a: "))
b = int(input("Enter value of b: "))
print(f"\na is {a} b is {b}")
a = a + b
b = a - b
a = a - b
print("\nafter swapping")
print(f"a is {a} b is {b}")

Program Explanation:

• Here we have used some logic and opearators to achieve our goal.

num1 = int(input("Enter starting range: "))
num2 = int(input("Enter ending range: "))
eve_count = 0
odd_count = 0
for i in range(num1, num2):
    if i%2 == 0:
        eve_count += 1
    else:
        odd_count += 1
print(f"Even number counts is {eve_count}")
print(f"Odd number counts is {odd_count}")

Program Explanation:

• Here we are getting two inputs from the user which we will use as a start and end range for our range function.
• The modulus operator (%) returns the remainder after division.
• Hence if the number returning 0 after division by 2 means that number is the multiple of 2 and that is an even number.
• This way we are incrementing the eve_counter by one each time the condition goes true.
• And else if not, we are entering to else control statement and incrementing the odd_ counter by 1.

a = int(input("Enter value 1: "))
b = int(input("Enter value 2: "))
choice = {
    '1': a+b,
    '2': a-b
    }
z = input("Press 1 for Add & 2 for Subtract")
print(choice.get(z))

Program Explanation:

• Like other programming languages, there is no specific switch method in python.
• We can achieve this by using dictionary mapping.
• The approach we used is dictionary mapping.
• Dictionary is the same as an associative array of php, js etc.
• Here get function is used to get the value at a specific choice.

def acceleration(v1, v2, t1, t2):
    a = (v2 - v1) / (t2 - t1)
    return a

print(acceleration(0,10,0,20))
# 0.5

Program Explanation:

• The first three lines are where we create the function with three parameters
• A function definition is like a blueprint.
• Then in the last line, we are printing out the function output.
• The output is whatever is returned by the return statement.

val1 = int(input("Enter value 1: "))
val2 = int(input("Enter value 2: "))
val3 = int(input("Enter value 3: "))
print("\n before sorting",val1, val2, val3)
s = []
s.append(int(val1))
s.append(int(val2))
s.append(int(val3))
s.sort()
print("\n after sorting",s)

Program Explanation:

• Here we are getting 3 values from the user and appending them into a list s[] using the append() method.
• There is an in-built function which sorts the value i.e. sort()
• Hence we used sort() function i.e sort() to sort values of list s[].
• Next, in else: part only those numbers will enter which are not multiples of 5. Hence we printed the values.
• Note: This program is valid only for integer type value.

for i in range(10,25):
    if i%5 == 0:
        pass
    else:
        print(i, end=" ")
# 11  12  13  14  16  17  18  19  21  22  23  24

Program Explanation:

• Here we used the range() function to iterate to a finite specific range from 10, 25.
• Next, we checked the condition ( if i%5 == 0) if the condition satisfies then it enters to if condition and in the if condition we used the pass keyword to skip that value.
• It means the number which is the multiple of 5 is skipped.
• Next, in else: part only those numbers will enter which are not multiples of 5. Hence we printed the values.
• Here end = ” “ used for blank spaces instead of next line.

x = int(input("Enter number to check: ")) # 3
a = [1,3,3,4,3,2,3]
count = 0
for i in range(len(a)):
    if a[i] == x:
        count = count+1 
print(f"{x} occurs {count} time")
# 3 occurs 4 time

Program Explanation:

• First, we took input from the user & stored that input value in x variable (suppose user entered 3).
• In the very next line, we created a list a[] with some demo elements.
• For loop is used for iteration. Each time loop executes the value of I increments by 1 and the max time loop iterates are the length of list a[].
• If the number 3 occurs in the list, the count variable increment by 1.
• Hence each time for loop executes and during its execution if number 3 occurs then count increments by 1.
• Hence we got the solution.

string_ = "adam is a boy and adam loves to play cricket."
x = input("Enter the word you want to check: ")
main = string_.split(" ")
count = 0
for i in range(len(main)):
    if main[i] == x:
        count += 1
print(count)
# adam occurs 2 time

Program Explanation:

• We split the string from empty space using the split() function of string.
• It returns the list as output.
• I.e. string “adam is a boy and adam loves to play cricket.” now converted to [‘adam’, ‘is’, ‘a’, ‘boy’, ‘and’, ‘adam’, ‘loves’, ‘to’, ‘play’, ‘cricket.’].
• Next, we iterated over each element of the list using for loop.
• We used a counter to increment the value by one each time value occurs in the list during iteration.

n = int(input("Enter number: "))
if n%2 == 0:
    print(f" {n} is Even number")
else:
    print(f" {n} is Odd number")

Program Explanation:

• The modulus operator (%) always returns the remainder after division.
• Hence we checked the condition if the number after division with 2 returns 0.
• If True means it is an even number else the number is odd.
• Please visit Operators in Python to learn more about modulus operator.

# Procedural approach
num1 = int(input("Enter number one ")) # 20
num2 = int(input("Enter number two ")) # 30
if(num1 * num2 == 500):
    print("The result is ",num1*num2)
else:
    print("The result is ",num1+num2)
# 50

# Functional approach
def exec(x,y):
    if(x*y < 500):
        print(x*y)
    else:
        print("The result is ",x+y)
exec(20,20)
# 400

num1 = int(input("Enter value 1: ")) # 10
num2 = int(input("Enter value 2: ")) # 30
num3 = int(input("Enter value 3: ")) # 20
if( num1 > num2 and num1 > num3):
    print(f"{num1} is greatest")
elif( num2 > num1 and num2 > num3):
    print(f"{num2} is greatest")
else:
    print(f"{num3} is greatest")
# 30 is greatest

# Functional approach
def exec(x,y):
    for i in range(x,y):
        if i%5 == 0:
            print(i, end=" ")
exec(10,50)
# 10 15 20 25 30 35 40 45 

# Functional approach
def exec(x):
    if(x[0] == x[len(x)-1]):
        print(True)
    else:
        print(False)

exec([1,2,3,4,5,6,7,1])
exec([1,2,3,4,5,6,7,8])
# True
# False

# Functional approach
def exec(fh):
    #Formula
    celcius = (fh-32)*5/9
    print(f"{fh} fahrenheit is equal to {celcius} celcius")
exec(50)
# 50 fahrenheit is equal to 10.0 celcius

# Functional approach
def exec(fh):
    for i in range(fh):
        for j in range(i):
            print("*",end=" ")
        print("\n")
exec(6)