How to Design Programs phần 8 doc

... master-check uses. Let us now study how the design recipe applies to the development of the program. The first step is to define the state variables and to specify the purpose of each variable. ... effects: (1) to initialize current-color; (2) to draw traffic light and ;; next : -> void ;; effects: (1) to change current-color from 'green to 'yellow, ;; &...

Ngày tải lên: 12/08/2014, 19:20

... versions of max with (list 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20) Explain the effect. Exercise 18. 2.13. Develop the function to- blue-eyed-ancestor. The function consumes a family ... tree (ftn) (see section 14.1) and produces a list that explains how to get to a blue-eyed ancestor. If there is no blue-eyed ancestor, the function produces false. TEAMFLY...

Ngày tải lên: 12/08/2014, 19:20

... estimate is to the actual area. Let us agree that R stands for the number of rectangles that we wish to consider. To determine how large these rectangles are, we need to figure out how large ... important to document the problem generation with good examples and to give a good termination argument. Exercise 26.3.5. Evaluate (quick-sort (list 10 6 8 9 14 12 3 11 14 16 2...

Ngày tải lên: 12/08/2014, 19:20

... individual traffic light. That is, in addition to switching from the current color to the next, an operator should be able to set a traffic light to red. The function for doing so already exists: ... effect: to change current-color from 'green to 'yellow, ;; 'yellow to 'red, and 'red to 'green (define (next) ) ;; next-color : TL-color -&...

Ngày tải lên: 12/08/2014, 19:20

... that show the reader how to analyze a problem statement; how to formulate concise goals; how to make up examples; how to develop an outline of the solution, based on the analysis; how to finish ... 8 Intermezzo 1: Syntax and Semantics 8. 2 The Scheme Vocabulary 8. 3 The Scheme Grammar 8. 4 The Meaning of Scheme 8. 5 Errors 8. 6 Boolean Expressions 8....

Ngày tải lên: 12/08/2014, 19:20

... need the two coordinates to compute the distance. Put differently, we know how to combine two numbers into a posn structure using make-posn and we don't know how to extract these numbers ... letters, however, is not enough because the program also needs to maintain a word that records how much the second player has guessed. The solution is to add one extra ``lette...

Ngày tải lên: 12/08/2014, 19:20

... inventory management: the cost of an inventory. In addition to a list of the available toys, a store owner should also maintain a list of the cost of each item. The cost list permits the owner to ... not draw-polygon . To get from the more general function to what we want, we need to figure out some way to connect the last dot to the first one. There are several ways to acc...

Ngày tải lên: 12/08/2014, 19:20

... 16.2.3. Show how to model a directory with two more attributes: a size and a systems attribute. The former measures how much space the directory itself (as opposed to its files and subdirectories) ... the two input lists together. Examples: (merge (list 1 3 5 7 9) (list 0 2 4 6 8) ) ;; expected value: (list 0 1 2 3 4 5 6 7 8 9) (merge (list 1 8 8 11 12) (list 2 3 4 8 13...

Ngày tải lên: 12/08/2014, 19:20

... counterexample. Consider the following table: plain factorial accumulator-style factorial 5.760 5.970 5. 780 5.940 5 .80 0 5. 980 5 .82 0 5.970 5 .87 0 6.690 5 .80 6 6.110 It represents the results for exercise ... vectors. A vector is a well-defined mathematical class of data with specific basic operations. For our purposes, it suffices to know how to construct them, how...

Ngày tải lên: 12/08/2014, 19:20

... accumulator ) ]))) (rem! a-hand0 ) )) The questions to ask now are what the accumulator represents and what its first value is. The best way to understand the nature of accumulators is to study ... accumulator empty) Now the pieces of the design puzzle fall into place. The complete definition of the function is in figure 123. The accumulator parameter is renamed to predeces...

Ngày tải lên: 12/08/2014, 19:20