Python Loop Programs with Solutions

90 loop programs from counting and digit tricks to star and letter patterns. They practise for, while, range(), break, continue and nested loops; every solution is explained and shows its real output.

All programs

• #1Numbers divisible by 7 and multiples of 5
  Write a Python program to find the numbers between 1500 and 2700 (both included) that are divisible by 7 and are multiples of 5.Easy
• #2Star pattern that grows then shrinks
  Write a Python program to print a star pattern that grows from 1 to 5 stars and shrinks back to 1, using nested loops.Easy
• #3Build a string character by character
  Write a Python program that adds each character of a word from the user to an empty string.Easy
• #4Count even and odd numbers
  Write a Python program to count the even and odd numbers in a series.Easy
• #5Print 0 to 6 except 3 and 6
  Write a Python program that prints all the numbers from 0 to 6 except 3 and 6.Easy
• #6Fibonacci series up to 20
  Write a Python program to print the Fibonacci series from 0 to 20.Easy
• #7FizzBuzz from 1 to 30
  Write a Python program that prints 1 to 30, but “Fizz” for multiples of 3, “Buzz” for multiples of 5 and “FizzBuzz” for multiples of both.Easy
• #8Convert uppercase letters to lowercase
  Write a Python program that converts all uppercase letters in a word to lowercase, using a loop.Easy
• #9Count letters and digits
  Write a Python program that counts the letters and digits in a string.Easy
• #10Letter O pattern
  Write a Python program to print the letter ‘O’ with stars.Medium
• #11Natural numbers 1 to n with while
  Write a Python program to print the natural numbers from 1 to n using a while loop.Easy
• #12Natural numbers n to 1 with while
  Write a Python program to print the natural numbers from n down to 1 using a while loop.Easy
• #13Print A to Z with chr()
  Write a Python program to print the alphabet from A to Z using a for loop and chr() (chr(65) is ‘A’).Easy
• #14Even numbers from 1 to 100
  Write a Python program to print all even numbers from 1 to 100.Easy
• #15Odd numbers from 1 to 100
  Write a Python program to print all odd numbers from 1 to 100.Easy
• #16Sum of 1 to n
  Write a Python program to find the sum of all natural numbers from 1 to n.Easy
• #17Sum of even numbers 1 to n
  Write a Python program to find the sum of all even numbers from 1 to n.Easy
• #18Sum of odd numbers 1 to n
  Write a Python program to find the sum of all odd numbers from 1 to n.Easy
• #19Count the digits of a number
  Write a Python program to count the digits of a number.Easy
• #20First and last digits
  Write a Python program to find the first and last digits of a number.Easy
• #21Sum of the first and last digits
  Write a Python program to find the sum of the first and last digits of a number.Easy
• #22Sum of digits
  Write a Python program to calculate the sum of the digits of a number.Easy
• #23Product of digits
  Write a Python program to calculate the product of the digits of a number.Easy
• #24Reverse a number
  Write a Python program to read a number and print its reverse.Easy
• #25Palindrome number with a loop
  Write a Python program to check whether a number is a palindrome using a loop.Easy
• #26Frequency of each digit
  Write a Python program to find how often each digit appears in an integer.Medium
• #27Number in words
  Write a Python program that prints each digit of a number as a word.Medium
• #28Power using a loop
  Write a Python program to calculate base raised to a power using a for loop.Easy
• #29Factors of a number
  Write a Python program to find all the factors of a number.Easy
• #30Factorial with a loop
  Write a Python program to calculate the factorial of a number using a loop.Easy
• #31Prime check with a loop
  Write a Python program to check whether a number is prime using a loop.Easy
• #32Primes from 1 to n
  Write a Python program to print all prime numbers from 1 to n.Easy
• #33Sum of primes from 1 to n
  Write a Python program to find the sum of all prime numbers from 1 to n.Easy
• #34Prime factors
  Write a Python program to find all prime factors of a number.Medium
• #35Armstrong number with a loop
  Write a Python program to check whether a number is an Armstrong number (153 = 1³ + 5³ + 3³) using a loop.Easy
• #36Armstrong numbers from 1 to n
  Write a Python program to print all Armstrong numbers from 1 to n.Medium
• #37Perfect number check
  Write a Python program to check whether a number is perfect: the sum of its factors (excluding itself) equals the number, like 28 = 1 + 2 + 4 + 7 + 14.Easy
• #38Perfect numbers from 1 to n
  Write a Python program to print all perfect numbers from 1 to n.Medium
• #39Fibonacci series of n terms
  Write a Python program to print the first n terms of the Fibonacci series.Easy
• #40Multiplication table
  Write a Python program to print the multiplication table of a number.Easy
• #41Letter T pattern
  Write a Python program to print the letter ‘T’ with stars: two full rows of 9 stars and a 3-star stem in the middle.Medium
• #42Number diamond pattern
  Write a Python program to print rows of numbers that grow from 1 to 5 numbers (1 to 15) and then shrink, counting back down (14 to 5).Hard
• #43Letter A pattern
  Write a Python program to print the letter ‘A’ with stars.Medium
• #44Star pyramid
  Write a Python program to print a pyramid of stars with 5 rows (1, 3, 5, 7, 9 stars).Easy
• #45Count even numbers 1 to 100
  Write a Python program to count the even numbers from 1 to 100.Easy
• #46Count odd numbers 1 to 100
  Write a Python program to count the odd numbers from 1 to 100.Easy
• #47Keep only the digits of the input
  Write a Python program that reads text and adds each digit to an empty list as a number.Easy
• #48Characters of a string into a list
  Write a Python program that adds every character of an input string to an empty list.Easy
• #49Taxi bill by distance
  Write a Python program to calculate a bill: first 5 km at Rs 15/km, next 20 km at Rs 12/km, after that Rs 10/km.Medium
• #50Electricity bill with slabs
  Write a Python program to calculate an electricity bill: first 50 units Rs 0.50, next 100 units Rs 0.75, next 100 units Rs 1.25, above 250 units Rs 1.50, plus a 17% surcharge.Medium
• #51Sum of odd numbers 1 to 100
  Write a Python program to calculate the sum of all odd numbers from 1 to 100.Easy
• #52Numbers from 0 to 100 divisible by 5
  Write a Python program to find the numbers from 0 to 100 divisible by 5.Easy
• #53Right triangle of stars
  Write a Python program to print a right triangle of stars with 5 rows.Easy
• #54Inverted right triangle of stars
  Write a Python program to print an inverted right triangle of stars with 5 rows.Easy
• #55Number triangle 1, 22, 333
  Write a Python program to print row i with the number i repeated i times, for i from 1 to 5, using nested loops.Easy
• #56Fibonacci numbers up to 55
  Write a Python program to print the first 11 Fibonacci numbers (0 to 55).Easy
• #57Validate a password
  Write a Python program to check a password: at least one lowercase letter, one uppercase letter, one digit, one of $ # @, and 5 to 15 characters long.Medium
• #58Does a string contain a digit?
  Write a Python program to check whether a string contains a digit.Easy
• #59Star triangle up and down
  Write a Python program to print stars growing from 1 to 5 and back to 1.Easy
• #60Table of 5 with a for loop
  Write a Python program to print the multiplication table of 5 with a for loop.Easy
• #61First 20 natural numbers
  Write a Python program to print the first 20 natural numbers with a for loop, separated by commas.Easy
• #62Display numbers from a list
  Write a Python program to display the numbers of a list separated by commas.Easy
• #63Each character on a new line
  Write a Python program to print each character of a string on a new line.Easy
• #64Even numbers 1-10 into a list
  Write a Python program that adds the even numbers from 1 to 10 into an empty list.Easy
• #65Odd numbers 1-10 into a list
  Write a Python program that adds the odd numbers from 1 to 10 into an empty list.Easy
• #66Print the keys of a dictionary
  Write a Python program to print the keys of a dictionary using a loop.Easy
• #67Print the values of a dictionary
  Write a Python program to print the values of a dictionary, capitalised.Easy
• #68Print keys and values
  Write a Python program to print the keys and values of a dictionary.Easy
• #69First 20 natural numbers with while
  Write a Python program to print the first 20 natural numbers using a while loop.Easy
• #70Table of 2 with a while loop
  Write a Python program to print the table of 2 using a while loop.Easy
• #71Sum of the first 10 numbers with while
  Write a Python program to find the sum of the first 10 natural numbers using a while loop.Easy
• #72Product of the first 10 numbers
  Write a Python program to find the product of the first 10 natural numbers.Easy
• #731 to 10 except 5 and 6 with while
  Write a Python program to print 1 to 10 except 5 and 6 using a while loop.Easy
• #74Days of the week except Sunday
  Write a Python program to print the days of the week except Sunday using a while loop.Easy
• #75Count special characters
  Write a Python program to count the special characters (not letters, digits or spaces) in a string.Easy
• #76Copy even numbers to a new list
  Write a Python program to copy the even numbers from a list into an empty list.Easy
• #77Copy odd numbers to a new list
  Write a Python program to copy the odd numbers from a list into an empty list.Easy
• #78Copy special characters to a new list
  Write a Python program to copy the special characters from a list into an empty list.Easy
• #79Last element with a while loop
  Write a Python program to print the last element of a list using a while loop.Easy
• #80Stop at 6 with a while loop
  Write a Python program to print 1 to 10 but stop when the number is 6, using a while loop.Easy
• #81Stop at 6 with a for loop
  Write a Python program to print 1 to 10 but stop when the number is 6, using a for loop.Easy
• #82Count characters in a file
  Write a Python program to count the characters in a file (letters, digits, punctuation and spaces, not counting newlines).Easy
• #83Count digits in a file
  Write a Python program to count the digits in a file.Easy
• #84Count uppercase letters in a file
  Write a Python program to count the uppercase letters in a file.Easy
• #85Count special characters in a file
  Write a Python program to count the special characters in a file.Easy
• #86Sort a list with loops
  Write a Python program to sort a list using loops (without sort()).Medium
• #87Copy and sort descending
  Write a Python program to copy elements from one list into an empty list and print them in descending order.Easy
• #88Maximum number in a list
  Write a Python program to find the largest number in a list using a loop.Easy
• #89Uppercase letter diamond
  Write a Python program to print the letters A to Y in rows of 1, 2, 3, 4, 5, 4, 3, 2, 1 letters.Medium
• #90Lowercase letter diamond
  Write a Python program to print the letters a to y in rows of 1, 3, 5, 7, 5, 3, 1 letters.Medium