1.3 Array Operations | Deletion from Array |
Explanation with Code | Data Structure
Jenny's Lectures CS IT
I will discuss the deletion operation using the example I used in a
previous video. Understanding how to delete data from a specific
position will also make it easier to delete data from the beginning or
end of the array. I declared an array of size 50 in the previous code, and
the memory manager allocated 200 bytes of memory for this array. One
variable, size, is used to determine the maximum size of the array. If the
user wants to insert only 10 or 5 elements, for example, I will ask them
how much size they want for the array, and this will allocate an
additional 4 bytes of memory. The user will then enter the elements of
the array, which will be initialized at runtime. To delete data from the
array, I will ask the user from which position they want to del ete the
data. For example, if they want to delete data from position 2, I will shift
the values from position 3 to 4 and reduce the size of the array by 1. I
will start a loop from the position to be deleted to the end of the array
and shift the values to the left. To print the updated array after deletion,
I will use a for loop to print each element of the array. It's important to
check the validity of the position entered by the user before deleting
data from the array. If the position is invalid, such as -1 or greater than
the size of the array, I will print "invalid position". If there is no data in
the array, it's also an underflow condition and the data cannot be
deleted. When deleting data from the end of the array, I will simply
decrement the size of the array. When deleting data from the beginning
of the array, I will shift all the elements to the left and decrement the
size of the array. The time complexity of the deletion operation depends
on the position from which the data is to be deleted. If th e data is to be
deleted from a specific position, all the elements to the right of that
position must be shifted to the left, which takes O(n) time. However, if
the array is unsorted, a quicker algorithm is to pick the last element of
the array and put it in the position to be deleted. The best algorithm for
this case takes constant time, which is O(1).
Explanation with Code | Data Structure
Jenny's Lectures CS IT
I will discuss the deletion operation using the example I used in a
previous video. Understanding how to delete data from a specific
position will also make it easier to delete data from the beginning or
end of the array. I declared an array of size 50 in the previous code, and
the memory manager allocated 200 bytes of memory for this array. One
variable, size, is used to determine the maximum size of the array. If the
user wants to insert only 10 or 5 elements, for example, I will ask them
how much size they want for the array, and this will allocate an
additional 4 bytes of memory. The user will then enter the elements of
the array, which will be initialized at runtime. To delete data from the
array, I will ask the user from which position they want to del ete the
data. For example, if they want to delete data from position 2, I will shift
the values from position 3 to 4 and reduce the size of the array by 1. I
will start a loop from the position to be deleted to the end of the array
and shift the values to the left. To print the updated array after deletion,
I will use a for loop to print each element of the array. It's important to
check the validity of the position entered by the user before deleting
data from the array. If the position is invalid, such as -1 or greater than
the size of the array, I will print "invalid position". If there is no data in
the array, it's also an underflow condition and the data cannot be
deleted. When deleting data from the end of the array, I will simply
decrement the size of the array. When deleting data from the beginning
of the array, I will shift all the elements to the left and decrement the
size of the array. The time complexity of the deletion operation depends
on the position from which the data is to be deleted. If th e data is to be
deleted from a specific position, all the elements to the right of that
position must be shifted to the left, which takes O(n) time. However, if
the array is unsorted, a quicker algorithm is to pick the last element of
the array and put it in the position to be deleted. The best algorithm for
this case takes constant time, which is O(1).
