HOMEWORK SET #$5($FOR EXTRA CREDIT$)$

ANSWER ALL QUESTIONS. Name: $q,$

$[6$ pts$]$ The following operations are performed on a stack: PUSH A$,$ PUSH B$,$ PUSH C$,$ POP, POP, PUSH D$,$ PUSH E$,$ POP, PUSH E$,$ PUSH F$,$ POP, POP, PUSH G

a$.$ What does the stack contain after the PUSH G$?$

b$.$ At which point does the stack contain the most elements? Without removing the elements left on the stack from the previous operations, we perform:

PUSH H$,$ PUSH I, PUSH J$,$ PUSH K$,$ POP, PUSH L$,$ POP, POP, POP, PUSH M$,$ POP, POP, PUSH M

c$.$ What does the stack contain now?

$[6$ pts$]$ The input stream of a stack is a list of all the elements we pushed onto the stack, in the order that we pushed them.

The output stream is a list of all the elements that are popped off the stack, in the order that they are popped off.

a$.$ What is the output stream from Exercise $1?$

b$.$ If the input stream is ZYXWVUTSR, create a sequence of pushes and pops such that the output stream is YXVUWZSRT.

c$.$ If the input stream is YXW$,$ how many different output streams can be created? List them down