If Statement in While Loop Javascript
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C++ Programming: Program Design Including Data Structures, Fifth Edition
C++ Programming: From Problem Analysis to Program Design, Fifth Edition Chapter 5: Control Structures II (Repetition) Objectives In this chapter, you will: • Learn about repetition (looping) control structures • Explore how to construct and use count- controlled, sentinel-controlled, flag- controlled, and EOF-controlled repetition structures • Examine break and continue statements • Discover how to form and use nested control structures C++ Programming: From Problem Analysis to Program Design, Fifth Edition 2 Objectives (cont'd.) • Learn how to avoid bugs by avoiding patches • Learn how to debug loops C++ Programming: From Problem Analysis to Program Design, Fifth Edition 3 Why Is Repetition Needed? • Repetition allows you to efficiently use variables • Can input, add, and average multiple numbers using a limited number of variables • For example, to add five numbers: – Declare a variable for each number, input the numbers and add the variables together – Create a loop that reads a number into a variable and adds it to a variable that contains the sum of the numbers C++ Programming: From Problem Analysis to Program Design, Fifth Edition 4 while Looping (Repetition) Structure • The general form of the while statement is: while is a reserved word • Statement can be simple or compound • Expression acts as a decision maker and is usually a logical expression • Statement is called the body of the loop • The parentheses are part of the syntax C++ Programming: From Problem Analysis to Program Design, Fifth Edition 5 while Looping (Repetition) -
7. Control Flow First?
Copyright (C) R.A. van Engelen, FSU Department of Computer Science, 2000-2004 Ordering Program Execution: What is Done 7. Control Flow First? Overview Categories for specifying ordering in programming languages: Expressions 1. Sequencing: the execution of statements and evaluation of Evaluation order expressions is usually in the order in which they appear in a Assignments program text Structured and unstructured flow constructs 2. Selection (or alternation): a run-time condition determines the Goto's choice among two or more statements or expressions Sequencing 3. Iteration: a statement is repeated a number of times or until a Selection run-time condition is met Iteration and iterators 4. Procedural abstraction: subroutines encapsulate collections of Recursion statements and subroutine calls can be treated as single Nondeterminacy statements 5. Recursion: subroutines which call themselves directly or indirectly to solve a problem, where the problem is typically defined in terms of simpler versions of itself 6. Concurrency: two or more program fragments executed in parallel, either on separate processors or interleaved on a single processor Note: Study Chapter 6 of the textbook except Section 7. Nondeterminacy: the execution order among alternative 6.6.2. constructs is deliberately left unspecified, indicating that any alternative will lead to a correct result Expression Syntax Expression Evaluation Ordering: Precedence An expression consists of and Associativity An atomic object, e.g. number or variable The use of infix, prefix, and postfix notation leads to ambiguity An operator applied to a collection of operands (or as to what is an operand of what arguments) which are expressions Fortran example: a+b*c**d**e/f Common syntactic forms for operators: The choice among alternative evaluation orders depends on Function call notation, e.g. -
While Statement in C
While Statement In C EnricoIs Reg alwaysdisheartening deplete or his novel aspects when chagrined luminesced disputatiously, some crayfishes he orbits clump so temporizingly? grindingly. Solid Ring-necked and comose Bennet Brendan tarnishes never tensehalf-and-half his Stuttgart! while Thank you use a counter is a while loop obscures the condition which is evaluated to embed videos in while c program C while loops statement allows to repeatedly run at same recipient of code until a wrap is met while loop is empty most basic loop in C programming while loop. We then hand this variable c in the statement block and represent your value for each. While adultery in C Set of instructions given coil the compiler to night set of statements until condition becomes false is called loops. If it is negative number added to the condition in c language including but in looping structures, but is executed infinite loop! While Loop Definition Example & Results Video & Lesson. While talking in C Know Program. What is the while eternal in C? A while loop around loop continuously and infinitely until the policy inside the parenthesis becomes false money must guard the. C while and dowhile Loop Programiz. Programming While Loop. The widow while redeem in the C language is basically a post tested loop upon the execution of several parts of the statements can be repeated by reckless use children do-while. 43 Loops Applications in C for Engineering Technology. Do it Loop in C Programming with Examples Phptpoint. Statements and display control C Tutorials Cpluspluscom. Do while just in c example program. -
A Survey of Hardware-Based Control Flow Integrity (CFI)
A survey of Hardware-based Control Flow Integrity (CFI) RUAN DE CLERCQ∗ and INGRID VERBAUWHEDE, KU Leuven Control Flow Integrity (CFI) is a computer security technique that detects runtime attacks by monitoring a program’s branching behavior. This work presents a detailed analysis of the security policies enforced by 21 recent hardware-based CFI architectures. The goal is to evaluate the security, limitations, hardware cost, performance, and practicality of using these policies. We show that many architectures are not suitable for widespread adoption, since they have practical issues, such as relying on accurate control flow model (which is difficult to obtain) or they implement policies which provide only limited security. CCS Concepts: • Security and privacy → Hardware-based security protocols; Information flow control; • General and reference → Surveys and overviews; Additional Key Words and Phrases: control-flow integrity, control-flow hijacking, return oriented programming, shadow stack ACM Reference format: Ruan de Clercq and Ingrid Verbauwhede. YYYY. A survey of Hardware-based Control Flow Integrity (CFI). ACM Comput. Surv. V, N, Article A (January YYYY), 27 pages. https://doi.org/10.1145/nnnnnnn.nnnnnnn 1 INTRODUCTION Today, a lot of software is written in memory unsafe languages, such as C and C++, which introduces memory corruption bugs. This makes software vulnerable to attack, since attackers exploit these bugs to make the software misbehave. Modern Operating Systems (OSs) and microprocessors are equipped with security mechanisms to protect against some classes of attacks. However, these mechanisms cannot defend against all attack classes. In particular, Code Reuse Attacks (CRAs), which re-uses pre-existing software for malicious purposes, is an important threat that is difficult to protect against. -
Control-Flow Analysis of Functional Programs
Control-flow analysis of functional programs JAN MIDTGAARD Department of Computer Science, Aarhus University We present a survey of control-flow analysis of functional programs, which has been the subject of extensive investigation throughout the past 30 years. Analyses of the control flow of functional programs have been formulated in multiple settings and have led to many different approximations, starting with the seminal works of Jones, Shivers, and Sestoft. In this paper, we survey control-flow analysis of functional programs by structuring the multitude of formulations and approximations and comparing them. Categories and Subject Descriptors: D.3.2 [Programming Languages]: Language Classifica- tions—Applicative languages; F.3.1 [Logics and Meanings of Programs]: Specifying and Ver- ifying and Reasoning about Programs General Terms: Languages, Theory, Verification Additional Key Words and Phrases: Control-flow analysis, higher-order functions 1. INTRODUCTION Since the introduction of high-level languages and compilers, much work has been devoted to approximating, at compile time, which values the variables of a given program may denote at run time. The problem has been named data-flow analysis or just flow analysis. In a language without higher-order functions, the operator of a function call is apparent from the text of the program: it is a lexically visible identifier and therefore the called function is available at compile time. One can thus base an analysis for such a language on the textual structure of the program, since it determines the exact control flow of the program, e.g., as a flow chart. On the other hand, in a language with higher-order functions, the operator of a function call may not be apparent from the text of the program: it can be the result of a computation and therefore the called function may not be available until run time. -
Chapter 6 Flow of Control
Chapter 6 Flow of Control 6.1 INTRODUCTION “Don't you hate code that's In Figure 6.1, we see a bus carrying the children to not properly indented? school. There is only one way to reach the school. The Making it [indenting] part of driver has no choice, but to follow the road one milestone the syntax guarantees that all after another to reach the school. We learnt in Chapter code is properly indented.” 5 that this is the concept of sequence, where Python executes one statement after another from beginning to – G. van Rossum the end of the program. These are the kind of programs we have been writing till now. In this chapter Figure 6.1: Bus carrying students to school » Introduction to Flow of Control Let us consider a program 6-1 that executes in » Selection sequence, that is, statements are executed in an order in which they are written. » Indentation The order of execution of the statements in a program » Repetition is known as flow of control. The flow of control can be » Break and Continue implemented using control structures. Python supports Statements two types of control structures—selection and repetition. » Nested Loops 2021-22 Ch 6.indd 121 08-Apr-19 12:37:51 PM 122 COMPUTER SCIENCE – CLASS XI Program 6-1 Program to print the difference of two numbers. #Program 6-1 #Program to print the difference of two input numbers num1 = int(input("Enter first number: ")) num2 = int(input("Enter second number: ")) diff = num1 - num2 print("The difference of",num1,"and",num2,"is",diff) Output: Enter first number 5 Enter second number 7 The difference of 5 and 7 is -2 6.2 SELECTION Now suppose we have `10 to buy a pen. -
While and Do-While Loops
While and Do-While Loops 15-110 Summer 2010 Margaret Reid-Miller Loops • Within a method, we can alter the flow of control using either conditionals or loops. • The loop statements while, do-while, and for allow us execute a statement(s) over and over. • Like a conditional, a loop is controlled by a boolean expression that determines how many times the statement is executed. E.g., You may want to calculate the interest paid on a mortgage for each year of the loan term. Summer 2010 15-110 (Reid-Miller) The while statement • The form of the while statement is while (<boolean_expression>) <statement> • If boolean_expression evaluates to true, then statement is executed. • Then, the boolean_expression is evaluated again. If it evaluates to true, statement is executed again. • This repetition continues until the boolean_expression evaluates to false. How is the while loop different from the if statement? Summer 2010 15-110 (Reid-Miller) The if Flowchart false boolean_expression true statement (body of loop) Summer 2010 15-110 (Reid-Miller) The while Flowchart false boolean_expression true statement (body of loop) Summer 2010 15-110 (Reid-Miller) A Example n = 5 while i output 0 Print n asterisks! i < n ? *! 1 int i = 0; ! i < n ? while (i < n) { ! ! **! System.out.print(“*”);! 2 i < n ? !i++;! ***! }! 3 i < n ? System.out.println();! ****! 4 i < n ? *****! 5 i < n ? ***** Summer 2010 15-110 (Reid-Miller) The Loop Control Variable • The variable i (known as the loop control variable) is used in three ways: it is initialized, tested, and updated.! -
Obfuscating C++ Programs Via Control Flow Flattening
Annales Univ. Sci. Budapest., Sect. Comp. 30 (2009) 3-19 OBFUSCATING C++ PROGRAMS VIA CONTROL FLOW FLATTENING T. L¶aszl¶oand A.¶ Kiss (Szeged, Hungary) Abstract. Protecting a software from unauthorized access is an ever de- manding task. Thus, in this paper, we focus on the protection of source code by means of obfuscation and discuss the adaptation of a control flow transformation technique called control flow flattening to the C++ lan- guage. In addition to the problems of adaptation and the solutions pro- posed for them, a formal algorithm of the technique is given as well. A prototype implementation of the algorithm presents that the complexity of a program can show an increase as high as 5-fold due to the obfuscation. 1. Introduction Protecting a software from unauthorized access is an ever demanding task. Unfortunately, it is impossible to guarantee complete safety, since with enough time given, there is no unbreakable code. Thus, the goal is usually to make the job of the attacker as di±cult as possible. Systems can be protected at several levels, e.g., hardware, operating system or source code. In this paper, we focus on the protection of source code by means of obfuscation. Several code obfuscation techniques exist. Their common feature is that they change programs to make their comprehension di±cult, while keep- ing their original behaviour. The simplest technique is layout transformation [1], which scrambles identi¯ers in the code, removes comments and debug informa- tion. Another technique is data obfuscation [2], which changes data structures, 4 T. L¶aszl¶oand A.¶ Kiss e.g., by changing variable visibilities or by reordering and restructuring arrays. -
Autocoding Methods for Networked Embedded Systems
University of Warwick institutional repository: http://go.warwick.ac.uk/wrap A Thesis Submitted for the Degree of PhD at the University of Warwick http://go.warwick.ac.uk/wrap/36892 This thesis is made available online and is protected by original copyright. Please scroll down to view the document itself. Please refer to the repository record for this item for information to help you to cite it. Our policy information is available from the repository home page. Innovation Report AUTOCODING METHODS FOR NETWORKED EMBEDDED SYSTEMS Submitted in partial fulfilment of the Engineering Doctorate By James Finney, 0117868 November 2009 Academic Supervisors: Dr. Peter Jones, Ross McMurran Industrial Supervisor: Dr. Paul Faithfull Declaration I have read and understood the rules on cheating, plagiarism and appropriate referencing as outlined in my handbook and I declare that the work contained in this submission is my own, unless otherwise acknowledged. Signed: …………………………………………………………………….James Finney ii Acknowledgements I would like to thank Rapicore Ltd and the EPSRC for funding this project. I would also like to offer special thanks to my supervisors: Dr. R.P. Jones, Dr. P. Faithfull, and R. McMurran, for their time, support, and guidance throughout this project. iii Table of Contents Declaration ....................................................................................................................... ii Acknowledgements ......................................................................................................... iii Figures -
Basically Speaking
'' !{_ . - -,: s ' �"-� . ! ' , ) f MICRO VIDEQM P.O. (.t�Box 7357 204 E. Washington St. · Ann Arbor, MI 48107 BASICALLY SPEAKING A Guide to BASIC Progratntning for the INTERACT Cotnputer MICRO VIDEqM P.O. �Box � 7357 204 E. Washington St. Ann Arbor, Ml 48107 BASICALLY SPEAKING is a publication of Micro Video Corporation Copyright 1980 , Micro Video Corporation Copyright 1978 , Microsoft All Rights Reserved First Printing -- December 1980 Second Printing -- April 1981 (Revisions) \. BASICALLY SPEAKING A Guide to BASIC Programming for the Interact Computer Table of Contents Chapter 1 BASIC Basics......................................................... 1-1 The Three Interact BASIC Languages ................................ 1-11 BASIC Dialects .................................................... 1-12 Documentation Convent ions ......................................... 1-13 Chapter 2 HOW TO SPEAK BASIC................................................... 2-1 DIRECT MODE OPERATION. 2-2 Screen Control 2-4 .........................................•....... Screen Layout .................................................. 2-5 Graphics Commands . ............................................. 2-6 Sounds and Music............................................... 2-8 Funct ions ...................................................... 2-9 User-defined Functions ......................................... 2-12 INDIRECT MODE OPERATION . 2-13 Program Listings............................................... 2-14 Mu ltiple Statements on a Single Line .......................... -
Control Flow Statements
Control Flow Statements Christopher M. Harden Contents 1 Some more types 2 1.1 Undefined and null . .2 1.2 Booleans . .2 1.2.1 Creating boolean values . .3 1.2.2 Combining boolean values . .4 2 Conditional statements 5 2.1 if statement . .5 2.1.1 Using blocks . .5 2.2 else statement . .6 2.3 Tertiary operator . .7 2.4 switch statement . .8 3 Looping constructs 10 3.1 while loop . 10 3.2 do while loop . 11 3.3 for loop . 11 3.4 Further loop control . 12 4 Try it yourself 13 1 1 Some more types 1.1 Undefined and null The undefined type has only one value, undefined. Similarly, the null type has only one value, null. Since both types have only one value, there are no operators on these types. These types exist to represent the absence of data, and their difference is only in intent. • undefined represents data that is accidentally missing. • null represents data that is intentionally missing. In general, null is to be used over undefined in your scripts. undefined is given to you by the JavaScript interpreter in certain situations, and it is useful to be able to notice these situations when they appear. Listing 1 shows the difference between the two. Listing 1: Undefined and Null 1 var name; 2 // Will say"Hello undefined" 3 a l e r t( "Hello" + name); 4 5 name= prompt( "Do not answer this question" ); 6 // Will say"Hello null" 7 a l e r t( "Hello" + name); 1.2 Booleans The Boolean type has two values, true and false. -
Control Flow Statements
Control Flow Statements http://docs.oracle.com/javase/tutorial/java/nutsandbolts/flow.html http://math.hws.edu/javanotes/c3/index.html 1 Control Flow The basic building blocks of programs - variables, expressions, statements, etc. - can be put together to build complex programs with more interesting behavior. CONTROL FLOW STATEMENTS break up the flow of execution by employing decision making, looping, and branching, enabling your program to conditionally execute particular blocks of code. Decision-making statements include the if statements and switch statements. There are also looping statements, as well as branching statements supported by Java. 2 Decision-Making Statements A. if statement if (x > 0) y++; // execute this statement if the expression (x > 0) evaluates to “true” // if it doesn’t evaluate to “true”, this part is just skipped // and the code continues on with the subsequent lines B. if-else statement - - gives another option if the expression by the if part evaluates to “false” if (x > 0) y++; // execute this statement if the expression (x > 0) evaluates to “true” else z++; // if expression doesn’t evaluate to “true”, then this part is executed instead if (testScore >= 90) grade = ‘A’; else if (testScore >= 80) grade = ‘B’; else if (testScore >= 70) grade = ‘C’; else if (testScore >= 60) grade = ‘D’; else grade = ‘F’; C. switch statement - - can be used in place of a big if-then-else statement; works with primitive types byte, short, char, and int; also with Strings, with Java SE7, (enclose the String with double quotes);