What is the name for the protocol data unit (pdu) of the data link layer?

Write a program that uses a widgetviewer object to do the following: generate two random integers between 1 and 9 (inclusive). name one of them x, the other y. display them to the user using jlabel objects. create a jlabel object displaying the text "enter an operation number." create a jtextfield for the user's input. create a jbutton displaying the text "press here when you've entered your operation." use addandwait to add it to the widgetviewer object. when the user clicks the jbutton, evaluate operation in the following order to determine the one and only mathematical operation to perform on x and y. use a jlabel to display the result. if operation is between 1 and 10 inclusive, add x and y. if operation is evenly divisible by 4, subtract y from x. if operation is evenly divisible by 5, use integer division to divide y into x. if operation is an even number, use floating point division to divide y into x. if none of the other tests on operation apply, multiply x and y. note: operation can be negative or zero.

We as humans write math expression in infix notation, e.g. 5 + 2 (the operators are written in-between the operands). in a computer’s language, however, it is preferred to have the operators on the right side of the operands, i.e. 5 2 +. for more complex expressions that include parenthesis and multiple operators, a compiler has to convert the expression into postfix first and then evaluate the resulting postfix.write a program that takes an “infix” expression as input, uses stacks to convert it into postfix expression, and finally evaluates it. it must support the following operations: + - / * ^ % (example infix expression: (7 - 3) / (2 + 2)postfix expression: 7 3 - 2 2 + /result: 1guidelines: 1. you will need to use stacks in three placesa. one for the parenthesis check [char stack]b. one during infix to postfix [char stack]c. one during evaluation [int stack]for a and b above, you can use same array and same push, pop method as both ofthem are char. but for evaluation you have int stack and you might consider to createanother push pop method to handle it. maybe push_int, pop_int, etc. or find otherstrategy to utilize existing push pop method2. you can create a function for obtaining operator priority. that function should take anoperator as input and return its priority as an integer. this function will you a lot andreduce repeated code3. during evaluation you will need to convert char into integer. example for single digit: char c = '5'; int x = c - '0';

Petrică, tânăr licean în clasa a ix-a, a primit în dar de la părinţii săi un cont bancar pentru micile sale cheltuieli curente. el este pasionat de internet banking şi îşi verifică cu grijă toate tranzacţiile efectuate. pentru creşterea securităţii tranzacţiilor online, banca îi furnizează lui petrică un număr pe care el va trebui să îl modifice, obţinând un număr tan – număr de autentificare a tranzacţiei (transaction authentication number). regula de obţinere a numărului tan este următoarea: se formează cel mai mic număr par din toate cifrele numărului furnizat de bancă. cerinţă cunoscând numărul n furnizat de bancă, să se determine numărul tan obţinut de petrică. date de intrare fişierul tan.in conţine pe prima linie numărul natural n cu semnificaţia din enunţ. date de ieşire fişierul de ieşire tan.out va conţine o singură linie pe care va fi scris numărul tan cerut. restricţii • 0 < n < 18*1018 • n are cel puţin o cifră pară • numărul tan obţinut nu poate conţine zerouri nesemnificative