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Answer = GUI (Graphical User Interface)
Answer:
c. StringBuilder
Explanation:
An alternative to the String class would be the StringBuilder Class. This class uses Strings as objects and allows you to mix and match different strings as well as adding, removing, implementing, and modifying strings themselves as though they were similar to an array. Unlike the string class StringBuilder allows you to modify and work with a combination of strings in the same piece of data as opposed to having various objects and copying pieces which would take up more memory.
Answer:
static int checkSymbol(char ch)
{
switch (ch)
{
case '+':
case '-':
return 1;
case '*':
case '/':
return 2;
case '^':
return 3;
}
return -1;
}
static String convertInfixToPostfix(String expression)
{
String calculation = new String("");
Stack<Character> operands = new Stack<>();
Stack<Character> operators = new Stack<>();
for (int i = 0; i<expression.length(); ++i)
{
char c = expression.charAt(i);
if (Character.isLetterOrDigit(c))
operands.push(c);
else if (c == '(')
operators.push(c);
else if (c == ')')
{
while (!operators.isEmpty() && operators.peek() != '(')
operands.push(operators.pop());
if (!operators.isEmpty() && operators.peek() != '(')
return NULL;
else
operators.pop();
}
else
{
while (!operators.isEmpty() && checkSymbol(c) <= checkSymbol(operators.peek()))
operands.push(operators.pop());
operators.push(c);
}
}
while (!operators.isEmpty())
operands.push(operators.pop());
while (!operands.isEmpty())
calculation+=operands.pop();
calculation=calculation.reverse();
return calculation;
}
Explanation:
- Create the checkSymbol function to see what symbol is being passed to the stack.
- Create the convertInfixToPostfix function that keeps track of the operands and the operators stack.
- Use conditional statements to check whether the character being passed is a letter, digit, symbol or a bracket.
- While the operators is not empty, keep pushing the character to the operators stack.
- At last reverse and return the calculation which has all the results.
There are two types of secondary memories.
- RAM
- ROM
RAM:
- RAM stands for random access memory .
- It is expandable.
- we can do multiple things in it.
- Its erasable.
ROM
- ROM stands for read only memory.
- It is permanent .
- We can only read in it.
- Its permanent hence not removable.
