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Lakshmi Pritha Nadesan
Lakshmi Pritha Nadesan

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Day 11 - Looping exercises

Here are some while loop questions focused on numbers for practice:

Basic Problems

1.Print Numbers
Write a program to print numbers from 1 to 10 using a while loop.

def print_number(no):
    num=1
    while num<=no:
        print(num, end=" ")
        num+=1
print_number(10)

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1 2 3 4 5 6 7 8 9 10
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2.Sum of N Numbers
Write a program to calculate the sum of the first NN natural numbers using a while loop.

def sum_of_number(no):
    num=1
    total=0
    while num<=no:
        total=total+num
        num+=1
    return total
no=int(input("Sum of the number:"))
print(sum_of_number(no))
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Sum of the number:10
55
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3.Even Numbers
Write a program to print all even numbers between 1 and 50 using a while loop.

def print_even_number(no):
    num=2
    while num<=no:
        print(num, end=" ")
        num+=2
print_even_number(50)

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2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 
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4.Odd Numbers
Write a program to print all odd numbers between 1 and NN.

def print_odd_number(no):
    num=1
    while num<=no:
        print(num, end=" ")
        num+=2
    return no
no=int(input("Enter the number:"))
print_odd_number(no)
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Enter the number:20
1 3 5 7 9 11 13 15 17 19
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5.Reverse Count
Write a program to print numbers from 20 to 1 in reverse order using a while loop.

def print_reverse_number(no):
    num=20
    while num>=no:
        print(num, end=" ")
        num-=1
print_reverse_number(1)
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20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 
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Intermediate Problems

1.Factorial Calculation
Write a program to calculate the factorial of a given number using a while loop.

def find_factorial(num):
    no=1
    factorial=1
    while no<=num:
        factorial=factorial*no
        no+=1
    return factorial
num=int(input("Enter the number:"))
print(find_factorial(num))
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Enter the number:5
120
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  1. Sum of Digits Write a program to find the sum of the digits of a given number (e.g., 123 → 1+2+3=6).
def sum_of_digits(num):
    sum=0
    while num>0:
        sum=sum+num%10
        num=num//10
    return sum
num=int(input("Enter the number:"))
print(sum_of_digits(num))
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Enter the number:123
6
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3.Count Digits
Write a program to count the number of digits in a given number (e.g., 12345 → 5 digits).

def count_of_digits(num):
    count=0
    while num>0:
        num=num//10
        count+=1
    return count
num=int(input("Enter the number:"))
print(count_of_digits(num))

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Enter the number:12345
5
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4.Reverse a Number
Write a program to reverse a given number (e.g., 123 → 321).

def reverse_number(num):
    reverse=0
    while num>0:
        reverse=reverse*10+num%10
        num=num//10
    return reverse
num=int(input("Enter the number:"))
print(reverse_number(num))
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Enter the number:123
321
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5.Multiplication Table
Write a program to print the multiplication table of a given number nn using a while loop.

def multiply(num):
    no=1
    while no<=15:
        print(no,"*",num,"=",no*num , end="\n")
        no+=1
num=int(input("Enter the number:"))
multiply(num)
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Enter the number:12
1 * 12 = 12
2 * 12 = 24
3 * 12 = 36
4 * 12 = 48
5 * 12 = 60
6 * 12 = 72
7 * 12 = 84
8 * 12 = 96
9 * 12 = 108
10 * 12 = 120
11 * 12 = 132
12 * 12 = 144
13 * 12 = 156
14 * 12 = 168
15 * 12 = 180
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Advanced Problems

1.Check Palindrome
Write a program to check if a given number is a palindrome (e.g., 121 → palindrome, 123 → not a palindrome).

def palindrome(num):
    count=0
    while num>0:
        count=count*10+num%10
        num=num//10
    return count
num=int(input("Enter the number:"))
result=palindrome(num)
if result==num:
    print("Palindrome")
else:
    print("Not palindrome")

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Enter the number:121
Palindrome
Enter the number:123
Not palindrome

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*2.Find the power *

def find_power(base,power):
    result=1
    while power>=1:
        result=result*base
        power-=1
    return result
base=int(input("Enter the base number:"))
power=int(input("Enter the power number:"))
result=find_power(base,power)
print(result)

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Enter the base number:2
Enter the power number:5
32
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3.Armstrong Number
Write a program to check if a given number is an Armstrong number (e.g., 153 → 13+53+33=15313+53+33=153).

def count_of_digits(num):
    count=0
    while num>0:
        num=num//10
        count+=1
    return count

def find_power(base,power):
    result=1
    while power>=1:
        result=result*base
        power-=1
    return result

def find_armstrong(num):
    armstrong=0
    while num>0:
        rem=num%10
        result= find_power(rem,count)
        armstrong=armstrong+result
        num=num//10
    return armstrong


num=int(input("Enter the number:"))
count=count_of_digits(num)
armstrong_result=find_armstrong(num)

if armstrong_result==num:
    print("Armstrong")
else:
    print("Not armstrong")
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Enter the number:123
Not armstrong
Enter the number:153
Armstrong

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4.Sum of even and odd position:

def sum_of_even_odd(num):
    odd=0
    even=0
    index=0
    while index<len(num):
        digit=int(num[index])
        if index%2==0:
            even=even+digit

        else:
            odd=odd+digit

        index+=1
    return even,odd

num=input("Enter the number:")
even,odd=sum_of_even_odd(num)
print("sum of even number:",even)
print("sum of odd number:",odd) 

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Enter the number:12345
sum of even number: 9
sum of odd number: 6

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