香港见闻共分享

jay2933UID: 2180435

苞米ms買到很多好吃的。。。

nobutsUID: 2210864

原帖由 jay2933 于 2006-10-31 00:47 发表
苞米ms買到很多好吃的。。。

是啊,以后晚上熬夜不用饿肚子了~~:victory:

nobutsUID: 2210864

鬱悶了！！什麽程序，BT死了！陳述得很模糊，搞得Newsgroup裏都是問題……
問題描述：

［————————————————————————————————————————］
COMP104: Assignment 2


|   11   |  2222  |  3333  |    44  | 555555 |  6666  | 777777 |  8888  |  9999  |  0000  |
|  111   | 22  22 | 33  33 |   444  | 55     | 66     |    77  | 88  88 | 99  99 | 00  00 |
|   11   |    22  |    33  |  4 44  | 55555  | 66666  |   77   |  8888  |  99999 | 00  00 |
|   11   |  222   | 33  33 | 444444 |    555 | 66  66 |  77    | 88  88 |     99 | 00  00 |
|  1111  | 222222 |  3333  |    44  | 55555  |  6666  | 77     |  8888  |  9999  |  0000  |


|   ++   |        | xx  xx |   //   |        |
|   ++   |        |  xxxx  |        | ====== |
| ++++++ | ------ |   xx   | ////// |        |
|   ++   |        |  xxxx  |        | ====== |
|   ++   |        | xx  xx |   //   |        |


Deadline: Nov 2 (Thursday), 11:55pm



0. Files to Download

    * assignment2-main.cpp
    * assignment2-function.cpp
    * big fonts (shown horizontally)
    * big fonts (shown vertically)

1. Task Objective

Write a C++ program to display an integer number or a binary expression of 2 integers in big fonts (as shown at the top).

The basic framework of the program is already written for you and is given in the file "assignment2-main.cpp". You need to complete the functions called by the main( ) function and write them in "assignment2-function.cpp".


2. Detailed Description
An expression can be given in 2 forms:

   1. a single integer; or,
   2. a binary expression consisting of 2 integers and a binary operator. Only 4 binary operators are supported:
          * '+' for addition
          * '-' for subtraction
          * '*' for multiplication
          * '/' for division

Note:

    * All integer numbers do not have leading unary '-' sign or unary '+' sign in both cases.
    * There can be many whitespaces around each operand and operator, but there is at least one whitespace before and after the operator.

If it is the first case with only a single number, there is no calculation to do. But if it is the second case, you will need to compute the result of the binary expression using integer arithmetic. Finally in both cases, you have to print the input(s) and the result in big fonts in different display styles.


2.1 Program Flow

   1. Print a welcome message (which is fixed already)
   2. Read expression
          * Check for possible input errors. If there are, print the corresponding error message and exit.
   3. If expression is a single integer,
          * Print the corresponding display options
          * Read user's choice
          * Display the number with the selected display style
   4. If the input expression is a binary expression,
          * Calculate the result of the expression
          * Print the corresponding display options
          * Read user's choice
          * Display the calculation with the selected display style


2.2 Examples of Legal Expressions

    In the following, double quotes are used to show the whitespaces embedded in the inputs. They are NOT supposed to appear in the actual testing environment.

    * "12368"
    * "3"
    * "             863   "
    * "345 - 987643"
    * "      2 * 444 "
    * "34                    /                        9                         "
    * "                    9        +  5"


2.3 Examples of Illegal Expressions

Example
        Reason
"1       2"
        there is no operator
"3+4"
        there are no whitespaces between the operands and the operator
"        345 @ 567 "
        the operator '@' is not supported
"abc - 124"         "abc" is not an integer
"45.6 + 99.8"         the operands are not integers but floating point numbers
"2E3 - 5E2"         scientific notation is not supported
"- 3"
        if it represents a single integer, then we don't support negative integer with unary minus sign. If it is a binary expression, then it should start with an integer, not an operator.


2.4 Display Styles

2.4.1 Display a Single Integer

If the input is a single integer number, say, 345, then there can be 4 display options:

   1. horizontal print: print the numbers in big fonts horizontally as

   2. vertical print: print the numbers in big fonts vertically as
   3. horizontal print plus moving back and forth (animation). It is like the first display but the display will move back and forth horizontally. (I'll demonstrate that in the class next week.)
   4. horizontal print plus moving up and down (animation). Again, it is like the first display but the display will move up and down. (I'll demonstrate that in the class next week.)


2.4.2 Display the Calculation of a Binary Expression

If the input is a binary integer expression, say, 54 / 3, then there can be 4 display options:

   1. horizontal print: print the calculation horizontally as

   2. vertical print: print the calculation vertically as
   3. vertical print plus moving back and forth (animation) : similarly to vertical print but the whole "picture" moves back and forth
   4. vertical print plus moving up and down (animation) : similarly to vertical print but the whole "picture" moves up and down


3. Some Specifications
3.1 Fixed Codes

Some codes are already written for you in the file assignment2-main.cpp. YOU ARE NOT ALLOWED TO MODIFY THEM. e.g.

    * the welcome message
    * the error messages, error codes
    * the display menus
    * the function prototypes of the given functions in assignment2-main.cpp


3.2 Big "Fonts" (Fixed)

The big "fonts" of the 10 digits and the 4 operators plus the "=" sign are given as shown at the top of this page. The '|' between each character is NOT part of the font; it is used to show the boundary between the characters. Each big character is 5 x 8, meaning that it consists of 5 rows and 8 columns. The first column and the 8th column are blank, so that when you want to print out two successive characters, you should not put any extra spaces between them.


3.3 Large Print

3.3.1 Large Horizontal Display of a Number/Calculation

No leading spaces, and no extra spaces between 2 characters.

3.3.2 Large Vertical Display of a Number

Put one blank line between 2 vertical characters.

3.3.3 Large Vertical Display of a Calculation

    * The operator must be on the left of all operands and result.
    * Put a line of "____________" (a separator of underscore symbols) between the 2nd operand and the result. The length of the separator line should be equal to the width of the longest line in the calculation.
    * There should be a blank line between the 1st operand and the 2nd operand, and between the separator line and the result.
    * But there is no blank line between the 2nd operand and the separator line.


3.4 Error Handling

When you read input expressions using the function

error_code read_expression(int& num_of_operands, char operand1[], char operand2[], my_operator& the_operator);

we only consider those types of errors as defined in the enumeration type

enum error_code {OKAY = 1, NOT_INTEGER, BAD_OPERATOR, TOO_MANY_DIGITS, TOO_FEW_OPERANDS, TOO_MANY_OPERANDS};

   1. OKAY: no error
   2. NOT_INTEGER: input operand/number is not an integer
   3. BAD_OPERATOR: unsupported operator
   4. TOO_MANY_DIGITS: the number of digits exceed the limit
   5. TOO_FEW_OPERANDS: Too few operands. There should be exactly 1 for single number and 2 for binary expression
   6. TOO_MANY_OPERANDS: more than 2 operands


      Examples

123456AB         NOT_INTEGER
123 + 456 * 789         TOO_MANY_OPERANDS
123 + 456 + 38         TOO_MANY_OPERANDS
123 +         TOO_FEW_OPERANDS
123 ^ 456         BAD_OPERATOR
123 456         BAD_OPERATOR (take 456 as operator)
123+456         NOT_INTEGER (no space between operands and operator, take "123+456" as 1st operand)
- 3         NOT_INTEGER ( take the 1st operand as "-" which is not integer)



    If the expression contains more than 1 error, return the first encountered error when the input is read from left to right.

    Examples
abc + 1234567890         NOT_INTEGER (operand not integer,  too many digits)
123 $ 4 5         BAD_OPERATOR (bad operator, too many operands)
123 4 + 789         BAD_OPERATOR (bad operator, too many operands)


3.5 Suggested Functions (not Mandatory but may be Helpful)

In this assignment, you are allowed to use any standard C++ library functions you like; make sure you include the right files. To handle character strings represented as 1D arrays, you may need the functions declared in string.h and stdlib.h.

Some other functions you may need:

bool is_digit(char c);                  // check if a character is a digit
bool is_operator(char c);               // check if a character is an operator
bool is_integer(char s[]);              // check if the string s is a number
bool string_to_int(char s[], int& n);   // convert a char array to int
bool int_to_string(int n, char s[]);    // convert an int to a char array (the number can be negative)
int get_string_size(char s[]);          // get the size of a string
void large_print_char(char c, int row); // print one row of character c


4. Hint on Animation
One way to do the animation is to write a while loop and make use of the following 3 functions to repeat some actions forever (one will stop with a control-c):

   1. call: system("clear");  // To clear the screen
   2. call the function usleep( ); // To sleep for a number of microseconds e.g. use REFRESH_RATE
   3. call the function you write to display the vertical print of the calculation

For details of the use of the usleep function, "man 3 usleep" on a lab2 Linux machine (or any Unix/Linux machine)



5. Extra Work for Bonus (+10%)
You may add up to 5 other display options (options 1-4 are reserved for the basic display modes, options 5-9 are open for your addition). The added options MUST be significantly different from the basic ones. For example, to display the calculation/number such that the calculation/number moves around the screen like a screensaver will do.

We will grade your bonus work according to its level of difficulty and complexity. Honestly speaking, how good your bonus work is can be very subjective; it is up to our judgement.


6. Assignment Submission

(A) ALL OF YOU HAVE TO DO THIS.

Complete the functions in the given assignment2-function.cpp, and submit the completed file: assignment2-function.cpp. You cannot modify the given assignment2-main.cpp file and you have to work under the limitations suggested by the codes in assignment2-main.cpp. In particular, you cannot modify the function prototypes of the functions that you are required to complete.

Your codes must be written in such a way that when we concatenate the given assignment2-main.cpp and your assignment2-function.cpp to, say, assignment2.cpp, the resulting file can be compiled and run in our lab2 Linux machines.

i.e. We will compile your codes using the following command

cat assignment2-main.cpp assignment2-function.cpp > assignment2.cpp
g++ -o assignment2 assignment2.cpp



(B) ONLY FOR THOSE WHO PLAN TO DO THE BONUS PART.

First submit the assignment2-function.cpp required by part (A). Then submit two additional files:

   1. assignment2-bonus.cpp :  a file similar to assignment2-function.cpp of part (A) but with additional display options. Basically it contains all the things in part (A) plus additional functions to support the additional display options.
   2. assignment2-bonus.txt :  an ASCII text file that we can read with the vi editor to explain
          * how many additional options you have added
          * what are the additional options
          * a brief description of what we will see for each of the additional display option

      i.e. We will compile your codes using the following command

      cat assignment2-main.cpp assignment2-bonus.cpp > assignment2x.cpp
      g++ -o assignment2x assignment2x.cpp


7. Miscellaneous
You have to submit the files by CASS. Here is the submission homepage of CASS:

https://course.cse.ust.hk/cass/student/submit.php

For details of submission via CASS, please visit:

http://cssystem.cse.ust.hk/home. ... s/cass/student.html

［————————————————————————————————————————］

Ｑｕｅｓｔｉｏｎｓ：
Case 1:   '0042'

  As Dr. Mak described in the Newsgroup as follows

"   In general, there are 2 choices:
1. since you don't allow leading zeros, you may treat integers with
leading zeros invalid integers.
2. you skip all leading zeros just like skipping white spaces before
reading an integer."

  Does it mean that either choice 1 or choice 2 will do? If it's the
second choice, do we take the leading zero(s) within the length of the
integer?

Case 2:   '1 ++ 2'

  What to do with the operator? Is it a bad operator or unknown error?

Case 3:   '1 + 2    /'

  The same goes with Case 2.

Case 4:   '123456789x'

  Should it be TOO_MANY_DIGITS or NOT_INTEGER?

Case 5:   '                        12                  '  

  The string length exceeds MAX_STR_LEN, what's the error message?

我快瘋了！

[ 本帖最后由 nobuts 于 2006-10-31 05:23 编辑 ]

nobutsUID: 2210864

居然九点睡十一点能醒……
上完课还有心情来上网~~~

qndqndqndUID: 2123528

好长的题目，回头我有空看看。

还要用unix编译？科大的计算机教育果然很正统。

nobutsUID: 2210864

原帖由 qndqndqnd 于 2006-10-31 13:57 发表
好长的题目，回头我有空看看。

还要用unix编译？科大的计算机教育果然很正统。

据说是今年刚改的,原来是用的VC++

qndqndqndUID: 2123528

>_<您老一个学期要写几份这样的"assignment”啊？

你趁早再弄个cs的三学位吧，趁早滴，我看你行……我不查library还不知道getline咋用呢>_<

qndqndqndUID: 2123528

你们说我该去写论文骗人呢，还是真刀真枪地找工作写程序去呢>_<貌似我做这种底层程序员一定会死呀

nobutsUID: 2210864

原帖由 qndqndqnd 于 2006-11-1 00:27 发表
>_<您老一个学期要写几份这样的"assignment”啊？

你趁早再弄个cs的三学位吧，趁早滴，我看你行……我不查library还不知道getline咋用呢>_<

我們一學期五個Assignment，第一次的也很變態，第三次的馬上要出來~~

qndqndqndUID: 2123528

原帖由 nobuts 于 2006-11-1 02:03 发表

8錯8錯~~能堅持到這份上已經很不容易了~~

后面的我连题目都还没看，一个第一题就搞死我。

刚才回来的路上想了想，基本知道怎么做了。

判断输入的算式是否合法，用以下步骤：

１、将整个算式过滤一遍，将连续出现的空格改成一个空格；

２、过滤之后，如果算式的第一位或最后一位是空格，就把空格删掉；

３、查找算式里剩下几个空格，如果没有空格，那么有可能是整数，如果有且只有两个空格，那么有可能是算式；

４、如果有可能是整数，且第一位是零，且算式长度等于１，则用户输入正确，算式就是“０”；

５、如果有可能是整数，且第一位是零、且算式长度大于１，则用户输入错误，NOT_INTEGER；

６、如果有可能是整数，且第一位不是零，那么查找整个算式中是否存在０～９以外的字符，如果存在，那么用户输入错误，NOT_INTEGER；

７、如果有可能是算式，那么根据算式里的两个空格将算式分成三块；

８、如果中间那部分长度大于１，那么用户输入错误；

９、如果中间那部分长度等于１，但是出现了非加减乘除以外的字符，那么用户输入错误；

１０、如果左边那部分第一位是零，且左边那部分算式长度等于１，则跳到步骤１３验证右边那部分算式；

１１、如果左边那部分第一位是零，且左边那部分算式长度大于１，则用户输入错误；

１２、如果左边那部分第一位不是零，那么查找左边整个算式中是否存在０～９以外的字符，如果存在，那么用户输入错误，反之跳到步骤１３检验右边那部分算式；

１３、如果右边那部分第一位是零，且右边那部分算式长度等于１，则用户输入正确，将左中右三部分分别转换格式后存入operand1、operatior、operand2；

１４、如果右边那部分第一位是零，且右边那部分算式长度大于１，则用户输入错误；

１５、如果右边那部分第一位不是零，那么查找右边整个算式中是否存在０～９以外的字符，如果存在，那么用户输入错误，反之用户输入正确，将左中右三部分分别转换格式后存入operand1、operator、operand2。

＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝

同志们，上面15步的逻辑只是第一题的第一步，我真的太低估这玩意了。

后面的题目我还没看，但大概意思就是要把算式画出来吧，还有那种立体的。

横排解法如下：

首先每个数字占位是5 * 8，而一个整数最多允许有8位，那么一个整数需要5 * 64格空间。

对于每一个数字和每一个符号都建立一个二维数组，把图形画进去。

建立三个5 * 64的空白数组用来储存两个operand和一个result，再建立一个5 * (64 * 3 + 16 * 2)的空白二维数组用来存最后的算式。

对于三个空白数组的填充方法就是把整数的各个位抄上去，对于整数n在百位的情况，对整数n的点阵内的每个点的坐标(i, j)进行如下换算：i = 8 * 6 + i, j保持不变。如果是个位的话就是8 * 8 + i。

最后把三个空白数组和两个运算符号添加到最后的算式图形里去。

为了避免三位数占掉八位数那么大的空间，对整个算式点阵的二维数组进行分析，如果有连续三个列为空白的话，就缩成两个列（最简单的就是把该位后面的所有字符往前移一格，然后以后再建个大小适当的空白数组再抄一遍进去。。

立体排列方法雷同，唯一不同的是在将结果存入最后算式的点阵前需要先对三个数字进行空白列删减，有连续三个列为空白的，就缩成两个列。不过在此前需要做的是比较三个数字的列的数目以确定最后立体图形的宽度，然后在删减的时候，当列的数目达到要求时就停止删减。

最后就是把几个图形拼到一起，因为图形高度都是固定的，就不难了，大不了三个数组分行输出三次就可以了。

qndqndqndUID: 2123528

原帖由 nobuts 于 2006-11-1 02:02 发表

我們一學期五個Assignment，第一次的也很變態，第三次的馬上要出來~~

我以前好像一学期14个assignment/exercise，不过都是小玩意。

这个是我第一个编程作业：

http://c4bbs.01www.com/assignment1.htm

那时候迟到两个星期，还没什么人愿意教我，太迟注册讲义都下不到……后来不知道怎么做出来的。:L

nobutsUID: 2210864

那個calculation的horizontal output已經搞定了~
單純數字的動畫也搞定了~
就差calculation的vertical output了~~

qndqndqndUID: 2123528

没看，不知道啥叫horizontal output和vertical output >_<，你们老师的英语好诡异。

qndqndqndUID: 2123528

歌曲：开学礼
歌手：李克勤 专辑：空中飞人


同学各位找个位
这是你的开学礼
望前看
想象戴着四方帽时多美丽
先交过难忘学费
先不会来年失礼
明天总会是个新学期
终生制
总要学无论代价多重
学会的多少帮补自信
背过书
何时被考起总有些用
至少你知道什么不懂
大概只得恋爱是
没标准的教科书
必须靠人不断试
学传情达意
二人共处才够真挚
同学各位找个位
这是你的开学礼
若然你生活有时过得苦仍不作弊
荆棘里完成学位
操守却仍然高贵
学懂的会是你毕业时
的优势
历遍艰辛不作弊
受苦也练成造艺
因此说人生在世
运程难预计
但能入世培养聪慧


[wmv]http://8tt.1hu.net/4/127/5487/263_0984.wma[/wmv]

nobutsUID: 2210864

原帖由 qndqndqnd 于 2006-11-1 05:40 发表
歌曲：开学礼
歌手：李克勤 专辑：空中飞人


同学各位找个位
这是你的开学礼
望前看
想象戴着四方帽时多美丽
先交过难忘学费
先不会来年失礼
明天总会是个新学期
终生制
总要学无论代价多重
学会的 ...

太能水了，你的精力太旺盛了，是不是用正常的體力學習，用紅牛支持的體力灌水？