21) What is the difference between a PUSH and a POP?
Pushing and popping applies to the way data is stored and retrieved in a stack. A push denotes data being added to it, meaning data is being “pushed” into the stack. On the other hand, a pop denotes data retrieval, and in particular refers to the topmost data being accessed.
22) What is a linear search?
A linear search refers to the way a target key is being searched in a sequential data structure. Using this method, each element in the list is checked and compared against the target key, and is repeated until found or if the end of the list has been reached.
23) How does variable declaration affect memory allocation?
The amount of memory to be allocated or reserved would depend on the data type of the variable being declared. For example, if a variable is declared to be of integer type, then 32 bits of memory storage will be reserved for that variable.
24) What is the advantage of the heap over a stack?
Basically, the heap is more flexible than the stack. That’s because memory space for the heap can be dynamically allocated and de-allocated as needed. However, memory of the heap can at times be slower when compared to that stack.
25) What is a postfix expression?
A postfix expression is an expression in which each operator follows its operands. The advantage of this form is that there is no need to group sub-expressions in parentheses or to consider operator precedence.
26) What is Data abstraction?
Data abstraction is a powerful tool for breaking down complex data problems into manageable chunks. This is applied by initially specifying the data objects involved and the operations to be performed on these data objects without being overly concerned with how the data objects will be represented and stored in memory.
27) How do you insert a new item in a binary search tree?
Assuming that the data to be inserted is a unique value (that is, not an existing entry in the tree), check first if the tree is empty. If it’s empty, just insert the new item in the root node. If it’s not empty, refer to the new item’s key. If it’s smaller than the root’s key, insert it into the root’s left subtree, otherwise, insert it into the root’s right subtree.
28) How does a selection sort work for an array?
The selection sort is a fairly intuitive sorting algorithm,, though not necessarily efficient. To perform this, the smallest element is first located and switched with the element at subscript zero, thereby placing the smallest element in the first position. The smallest element remaining in the subarray is then located next with subscripts 1 through n-1 and switched with the element at subscript 1, thereby placing the second smallest element in the second position. The steps are repeated in the same manner till the last element.
29) How do signed and unsigned numbers affect memory?
In the case of signed numbers, the first bit is used to indicate whether positive or negative, which leaves you with one bit short. With unsigned numbers, you have all bits available for that number. The effect is best seen in the number range (unsigned 8 bit number has a range 0-255, while 8-bit signed number has a range -128 to +127.
30) What is the minimum number of nodes that a binary tree can have?
A binary tree can have a minimum of zero nodes, which occurs when the nodes have NULL values. Furthermore, a binary tree can also have 1 or 2 nodes.
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Pushing and popping applies to the way data is stored and retrieved in a stack. A push denotes data being added to it, meaning data is being “pushed” into the stack. On the other hand, a pop denotes data retrieval, and in particular refers to the topmost data being accessed.
22) What is a linear search?
A linear search refers to the way a target key is being searched in a sequential data structure. Using this method, each element in the list is checked and compared against the target key, and is repeated until found or if the end of the list has been reached.
23) How does variable declaration affect memory allocation?
The amount of memory to be allocated or reserved would depend on the data type of the variable being declared. For example, if a variable is declared to be of integer type, then 32 bits of memory storage will be reserved for that variable.
24) What is the advantage of the heap over a stack?
Basically, the heap is more flexible than the stack. That’s because memory space for the heap can be dynamically allocated and de-allocated as needed. However, memory of the heap can at times be slower when compared to that stack.
25) What is a postfix expression?
A postfix expression is an expression in which each operator follows its operands. The advantage of this form is that there is no need to group sub-expressions in parentheses or to consider operator precedence.
26) What is Data abstraction?
Data abstraction is a powerful tool for breaking down complex data problems into manageable chunks. This is applied by initially specifying the data objects involved and the operations to be performed on these data objects without being overly concerned with how the data objects will be represented and stored in memory.
27) How do you insert a new item in a binary search tree?
Assuming that the data to be inserted is a unique value (that is, not an existing entry in the tree), check first if the tree is empty. If it’s empty, just insert the new item in the root node. If it’s not empty, refer to the new item’s key. If it’s smaller than the root’s key, insert it into the root’s left subtree, otherwise, insert it into the root’s right subtree.
28) How does a selection sort work for an array?
The selection sort is a fairly intuitive sorting algorithm,, though not necessarily efficient. To perform this, the smallest element is first located and switched with the element at subscript zero, thereby placing the smallest element in the first position. The smallest element remaining in the subarray is then located next with subscripts 1 through n-1 and switched with the element at subscript 1, thereby placing the second smallest element in the second position. The steps are repeated in the same manner till the last element.
29) How do signed and unsigned numbers affect memory?
In the case of signed numbers, the first bit is used to indicate whether positive or negative, which leaves you with one bit short. With unsigned numbers, you have all bits available for that number. The effect is best seen in the number range (unsigned 8 bit number has a range 0-255, while 8-bit signed number has a range -128 to +127.
30) What is the minimum number of nodes that a binary tree can have?
A binary tree can have a minimum of zero nodes, which occurs when the nodes have NULL values. Furthermore, a binary tree can also have 1 or 2 nodes.