shrink array size in the stack while we remove elements
$begingroup$
I am working on stack implementation where I need to shrink array size as objects are removed from the stack. Just like I increase the array size if it reaches it's default limit.
I need to implement two methods for this:
isBig: The first new method checks whether we should reduce the size of the array. This method returns true if the number of entries in the stack is less than half the size of the array and the size of the array is greater than 20.
reduce: This method creates a new array that is three quarters the size of the current array and then copies the objects in the bag to the new array.
And after implementing above two methods, I need to use them in the pop() method.
So I implemented isBig and reduce method basis on the above spec and using them in pop method.
Below is my code:
public class StackMethods {
private static final int LIMIT = 10;
private Integer stack;
private int index;
public StackMethods() {
this(LIMIT);
}
public StackMethods(int cap) {
Integer holder = (Integer) new Object[cap];
stack = holder;
index = -1;
}
@Override
public void push(Integer newEntry) {
checkCapacityLimit();
index++;
stack[index] = newEntry;
}
private void checkCapacityLimit() {
if (index == stack.length - 1)
stack = Arrays.copyOf(stack, 2 * stack.length);
}
@Override
public Integer pop() {
Integer top = null;
// this is how it will be used?
if (isBig()) {
reduce();
}
if (!isEmpty()) {
top = stack[index];
stack[index] = null;
index--;
}
return top;
}
// does this look right?
private boolean isBig() {
return ((index < stack.length / 2) && (stack.length > 20));
}
// does this look right as well?
private void reduce() {
stack = Arrays.copyOf(stack, 3 / 4 * stack.length);
}
}
Any better way to write isBig or reduce method here?
java algorithm
asked 7 mins ago
daviddavid
46252138
$endgroup$
add a comment |
$begingroup$
I am working on stack implementation where I need to shrink array size as objects are removed from the stack. Just like I increase the array size if it reaches it's default limit.
I need to implement two methods for this:
isBig: The first new method checks whether we should reduce the size of the array. This method returns true if the number of entries in the stack is less than half the size of the array and the size of the array is greater than 20.
reduce: This method creates a new array that is three quarters the size of the current array and then copies the objects in the bag to the new array.
And after implementing above two methods, I need to use them in the pop() method.
So I implemented isBig and reduce method basis on the above spec and using them in pop method.
Below is my code:
public class StackMethods {
private static final int LIMIT = 10;
private Integer stack;
private int index;
public StackMethods() {
this(LIMIT);
}
public StackMethods(int cap) {
Integer holder = (Integer) new Object[cap];
stack = holder;
index = -1;
}
@Override
public void push(Integer newEntry) {
checkCapacityLimit();
index++;
stack[index] = newEntry;
}
private void checkCapacityLimit() {
if (index == stack.length - 1)
stack = Arrays.copyOf(stack, 2 * stack.length);
}
@Override
public Integer pop() {
Integer top = null;
// this is how it will be used?
if (isBig()) {
reduce();
}
if (!isEmpty()) {
top = stack[index];
stack[index] = null;
index--;
}
return top;
}
// does this look right?
private boolean isBig() {
return ((index < stack.length / 2) && (stack.length > 20));
}
// does this look right as well?
private void reduce() {
stack = Arrays.copyOf(stack, 3 / 4 * stack.length);
}
}
Any better way to write isBig or reduce method here?
java algorithm
asked 7 mins ago
daviddavid
46252138
$endgroup$
add a comment |
$begingroup$
I am working on stack implementation where I need to shrink array size as objects are removed from the stack. Just like I increase the array size if it reaches it's default limit.
I need to implement two methods for this:
isBig: The first new method checks whether we should reduce the size of the array. This method returns true if the number of entries in the stack is less than half the size of the array and the size of the array is greater than 20.
reduce: This method creates a new array that is three quarters the size of the current array and then copies the objects in the bag to the new array.
And after implementing above two methods, I need to use them in the pop() method.
So I implemented isBig and reduce method basis on the above spec and using them in pop method.
Below is my code:
public class StackMethods {
private static final int LIMIT = 10;
private Integer stack;
private int index;
public StackMethods() {
this(LIMIT);
}
public StackMethods(int cap) {
Integer holder = (Integer) new Object[cap];
stack = holder;
index = -1;
}
@Override
public void push(Integer newEntry) {
checkCapacityLimit();
index++;
stack[index] = newEntry;
}
private void checkCapacityLimit() {
if (index == stack.length - 1)
stack = Arrays.copyOf(stack, 2 * stack.length);
}
@Override
public Integer pop() {
Integer top = null;
// this is how it will be used?
if (isBig()) {
reduce();
}
if (!isEmpty()) {
top = stack[index];
stack[index] = null;
index--;
}
return top;
}
// does this look right?
private boolean isBig() {
return ((index < stack.length / 2) && (stack.length > 20));
}
// does this look right as well?
private void reduce() {
stack = Arrays.copyOf(stack, 3 / 4 * stack.length);
}
}
Any better way to write isBig or reduce method here?
java algorithm
asked 7 mins ago
daviddavid
46252138
$endgroup$
I am working on stack implementation where I need to shrink array size as objects are removed from the stack. Just like I increase the array size if it reaches it's default limit.
I need to implement two methods for this:
isBig: The first new method checks whether we should reduce the size of the array. This method returns true if the number of entries in the stack is less than half the size of the array and the size of the array is greater than 20.
reduce: This method creates a new array that is three quarters the size of the current array and then copies the objects in the bag to the new array.
And after implementing above two methods, I need to use them in the pop() method.
So I implemented isBig and reduce method basis on the above spec and using them in pop method.
Below is my code:
public class StackMethods {
private static final int LIMIT = 10;
private Integer stack;
private int index;
public StackMethods() {
this(LIMIT);
}
public StackMethods(int cap) {
Integer holder = (Integer) new Object[cap];
stack = holder;
index = -1;
}
@Override
public void push(Integer newEntry) {
checkCapacityLimit();
index++;
stack[index] = newEntry;
}
private void checkCapacityLimit() {
if (index == stack.length - 1)
stack = Arrays.copyOf(stack, 2 * stack.length);
}
@Override
public Integer pop() {
Integer top = null;
// this is how it will be used?
if (isBig()) {
reduce();
}
if (!isEmpty()) {
top = stack[index];
stack[index] = null;
index--;
}
return top;
}
// does this look right?
private boolean isBig() {
return ((index < stack.length / 2) && (stack.length > 20));
}
// does this look right as well?
private void reduce() {
stack = Arrays.copyOf(stack, 3 / 4 * stack.length);
}
}
Any better way to write isBig or reduce method here?
java algorithm
java algorithm
asked 7 mins ago
daviddavid
46252138
asked 7 mins ago
daviddavid
46252138
asked 7 mins ago
daviddavid
46252138
asked 7 mins ago
daviddavid
46252138
asked 7 mins ago
daviddavid
46252138
46252138
add a comment |
add a comment |
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