Write a Python program to left rotate a list by n times or positions. In this example, we sliced the list using the position and combined it using arithmetic +.
ltList = [5, 10, 15, 20, 25, 30, 35, 40, 45, 50]
ltRotate = int(input("Enter Position to Left Rotate List Items = "))
print('Original List Items Before Left Rotating')
print(ltList)
list2 = ltList[ltRotate:] + ltList[:ltRotate]
print('\nFinal List Items After Left Rotating')
print(list2)
This Python program uses the for loop to left rotate the list elements by the user given position.
ltList = [11, 22, 33, 44, 55, 66, 77, 88]
ltRotate = int(input("Enter Position to Left Rotate List Items = "))
print('Original List Items Before Left Rotating')
print(ltList)
for i in range(ltRotate):
firstValue = ltList[0]
for j in range(len(ltList) - 1):
ltList[j] = ltList[j + 1]
ltList[len(ltList) - 1] = firstValue
print('Final List Items After Left Rotating')
print(ltList)
Enter Position to Left Rotate List Items = 6
Original List Items Before Left Rotating
[11, 22, 33, 44, 55, 66, 77, 88]
Final List Items After Left Rotating
[77, 88, 11, 22, 33, 44, 55, 66]This example allows the user to enter the list size, items, and rotation number, and left rotate the list items by a given number.
def printListItems(ltList):
for i in range(len(ltList)):
print(ltList[i], end = ' ')
ltList = []
ltListTot = int(input("Total Number of Left Rotate List Items = "))
for i in range(1, ltListTot + 1):
ltListvalue = int(input("Please enter the %d List Item = " %i))
ltList.append(ltListvalue)
ltRotate = int(input("Enter Position to Left Rotate List Items = "))
print('\nOriginal List Items Before Left Rotating')
printListItems(ltList)
for i in range(ltRotate):
firstValue = ltList[0]
for j in range(len(ltList) - 1):
ltList[j] = ltList[j + 1]
ltList[len(ltList) - 1] = firstValue
print('\nFinal List Items After Left Rotating')
printListItems(ltList)
Total Number of Left Rotate List Items = 7
Please enter the 1 List Item = 30
Please enter the 2 List Item = 40
Please enter the 3 List Item = 50
Please enter the 4 List Item = 70
Please enter the 5 List Item = 90
Please enter the 6 List Item = 120
Please enter the 7 List Item = 180
Enter Position to Left Rotate List Items = 2
Original List Items Before Left Rotating
30 40 50 70 90 120 180
Final List Items After Left Rotating
50 70 90 120 180 30 40 This Python program will help to left rotate a list by n using a while loop.
def printListItems(ltList):
i = 0
while i < len(ltList):
print(ltList[i], end = ' ')
i = i + 1
ltList = []
ltListTot = int(input("Total Number of Left Rotate List Items = "))
i = 1
while i <= ltListTot:
ltListvalue = int(input("Please enter the %d List Item = " %i))
ltList.append(ltListvalue)
i = i + 1
ltRotate = int(input("Enter Position to Left Rotate List Items = "))
print('\nOriginal List Items Before Left Rotating')
printListItems(ltList)
i = 0
while i < ltRotate:
firstValue = ltList[0]
j = 0
while j < len(ltList) - 1:
ltList[j] = ltList[j + 1]
j = j + 1
i = i + 1
ltList[len(ltList) - 1] = firstValue
print('\nFinal List Items After Left Rotating')
printListItems(ltList)
Total Number of Left Rotate List Items = 8
Please enter the 1 List Item = 23
Please enter the 2 List Item = 45
Please enter the 3 List Item = 67
Please enter the 4 List Item = 98
Please enter the 5 List Item = 89
Please enter the 6 List Item = 11
Please enter the 7 List Item = 16
Please enter the 8 List Item = 87
Enter Position to Left Rotate List Items = 3
Original List Items Before Left Rotating
23 45 67 98 89 11 16 87
Final List Items After Left Rotating
98 89 11 16 87 23 45 67