XI CS - FOR LOOP PRACTICE QUESTIONS

 

                                                  FOR LOOP PRACTICE QUESTIONS

1. WAP TO PRINT 10 8 6 4 2 AND SUM OF SERIES 

2.  WAP TO PRINT FIRST 20 EVEN NUMBERS AND PRINT THEIR SUM

3. WAP TO PRINT FACTORIAL OF A GIVEN NUMBER

SOLUTION:

n=int(input("Enter a number -"))

res =1

for i in range(1,n+1):

    res *= i

print(n," = ",res)

4. WAP TO PRINT EVEN NOS BETWEEN 2 GIVEN NOS

5. WAP TO INPUT NUMBERS & PRINT ITS FACTORS

SOLUTION:

n = int(input(“Enter a number -”))

for i in range(1,n+1):

    if (n%i==0):

        print("\t -",i)

6. WAP TO PRINT FIBONACCI  SERIES  : 0  1  1  2  3  5  8.....N TERMS

SOLUTION:

f, s = 0,1

n = int(input("Enter number of terms-"))

print(f, s , sep="\t ", end=" ")

for i in range(3,n+1):

    t = f + s

    print(t , end=" ")

    f, s = s, t                                        # f = s and s=t

7. Write a Python program to accept n number of integers from user. 

Count and display the number of odd, even and zero entered by the user. Accept n from user

SOLUTION:

8. WAP to input the value of n and calculate sum of the series:

1 / x² + 2 / x³ + 3 / x⁴ + …… n /x ⁿ⁺¹

SOLUTION:

n = int(input("Enter Value of n -"))

x = int(input("Enter Value of x -"))

sum = 0

for i in range(1,n+1):

sum + = i/ x ** (i+1)          # OR    t=x**i/i+1      sum+=t

else:

print("sum of series -",sum)

9. Write a program to input the value of n and calculate sum of the series:

1 + 2² + 3² + …… n²

SOLUTION:

n = int(input("Enter Value of n -"))

sum = 0

for i in range(1,n+1):

sum += i** 2

else:

print("sum of series -",sum)

10. Write code to check for perfect square . 

A perfect square is an integer that is the square of another integer 

$9$ is a perfect square because $3 \times 3 = 9$    Eg: 25 (5x5) , 36(6x6)

Solution:

n=int(input("Enter Number:"))

i = 1  

sq=False

while i * i <= n:  

        if i * i == n:  

           print("perfect square") 

           sq=True

           break

        i += 1      

if not sq:

    print("No") 

11. #WAP TO PRINT SUM OF DIGITS

num=int(input("Enter No"))

#123

ds=0

while num>0:

    ds=ds+num%10

    num=num//10

print("Sum of Digits:",ds)

12. Write a program to enter a number and check if it is a Harshad Number. A Harshad number is divisible by the sum of its digits. Eg.21,111,153

n = int(input("Enter Value of n -"))   

sum=0  

c=n                                                     

while n>0:                                          

     sum+= n%10                                 

     n//=10                                          

if c%sum==0:                                  

     print("Harshad number")

else:

    print("Not a Harshad number")

13. # Python program to check if the number is an Armstrong number or not

In case of an Armstrong number of 3 digits, the sum of cubes of each digit is equal to the number itself. For example: 153 = 1*1*1 + 5*5*5 + 3*3*3  // 153 is an Armstrong number.

# take input from the user

num = int(input("Enter a number: "))

# initialize sum

sum = 0

# find the sum of the cube of each digit

temp = num

while temp > 0:

   digit = temp % 10

   sum += digit ** 3

   temp //= 10

# display the result

if num == sum:

   print(num,"is an Armstrong number")

else:

   print(num,"is not an Armstrong number")

14.  # Python program to check if the number is a Palindrome number or not

eg: 12321 , 1234321

15. Mersenne numbers are a special class of integers that are one less than a power of two. 

M_n​=2ⁿ−1

Where n is a positive integer .

Eg:

If n=2 , 2²-1 , then 4-1=3

If n=3 , 2³-1, then 8-1=7

If n=4, 2⁴-1 , then 16-1=15

#Mersenne Number

n = int(input("Enter number"))

for i in range(1, n + 1):

    mersenne = 2**i - 1

    print("Mersenne number :",mersenne)