Introduction to Computer Science

1
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• ??????/???????/
• ???????????

2
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1. ???????
2. ??????
3. ????????????
4. ????
5. ???????
6. ????, ??if??, ?????
7. bool????????
8. ??????

3
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1. ???????
2. ??????
3. ????????????
4. ????
5. ???????
6. ????, ??if??, ?????
7. bool????????
8. ??????

4
????UsingVariable????

• char aChar 'a'
• Console.WriteLine(aChar)
• int anInt 123
• Console.WriteLine(anInt)
• double aDouble
• aDouble 123.456
• Console.WriteLine(aDouble)
• bool aBool true
• Console.WriteLine(aBool)

5
???????
J. G. Brookshear, Computer Science An
Overview, 8th edition, Addison-Wesley, 2005
6
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• ?????????
• ????
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• ????
• ????
• ??????
• ?? (Assignment) ???? (Initialization)
• ????

7
????UsingNumeric????

• int x 256
• Console.WriteLine("x " x)
• byte y 255
• Console.WriteLine("y " y)
• double z 123.45
• Console.WriteLine("z " z)
• float f 123.45f
• Console.WriteLine("f " f)
• decimal d 123.45m
• Console.WriteLine("d " d)

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????

• sbyte -128 127
• byte 0 255
• short -32768 32767
• unshort 0 65535
• int -2147483648 2147483647
• uint 0 4294967295
• long -9223372036854775808 9223372036854775807
• ulong 0 18446744073709551615
• char U0000 Uffff

9
?????

• float 7 ????, ??1.5e-45 3.4e38, 32 ??
• double 1516????, ??5.0e-324 1.7e308, 64 ??

0
10
decimal ??

• 28 29 ???, ??1.0e-28 7.9e28, 128 ??

11
????UsingChar????

• char c1 'a'
• char c2 '?'
• char c3 '\x0059'
• char c4 '\u0058'
• char c5 '\n'
• char c6 '\''

12
????

• ASCII vs. Unicode
• ?????Unicode???
• ????( Escaped character )
• \a ??(alarm)
• \b ??(backspace)
• \ ???(apostrophe)
• \\ ???(backslash)
• \t ????(tab)
• \n ??(next line)

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?????

• string s1 abc
• string s2 a
• char c a

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??(Stack)???(Heap)
. . .
Stack
15
????????
??(Stack)
int x 100
100
x
16
????????
??(Heap)
??(Stack)
string x abc
a
??
x
b
c
17
??

• ?????,?????????,?????

18
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1. ???????
2. ??????
3. ????????????
4. ????
5. ???????
6. ????, ??if??, ?????
7. bool????????
8. ??????

19
????Conversion????

• int a 10
• double b 0
• b a
• b 20.5
• a (int)b
• float c 20
• c 20.5f
• c (float)20.5
• char d (char)65

20
?????????

• ???? (Assignment)
• ???? (Implicit conversion)
• ???? (Explicit conversion)

21
??

1. ???????
2. ??????
3. ????????????
4. ????
5. ???????
6. ????, ??if??, ?????
7. bool????????
8. ??????

22
????UsingMathOperator????

• Console.WriteLine("?????????x ")
• int x int.Parse(Console.ReadLine())
• Console.WriteLine("?????????y ")
• int y int.Parse(Console.ReadLine())
• Console.WriteLine(" x y 0 ", x y)
• Console.WriteLine(" x - y 0 ", x - y)
• Console.WriteLine(" x y 0 ", x y)
• Console.WriteLine(" x / y 0 ", x / y)
• Console.WriteLine(" x y 0 ", x y)

23
???????

• ???(Operand)????(Operator)
• ?????(Assignment)
• ?????
• ???????
• ??
• ?????????

24
????????

• ?1
• byte bValue 254
• bValue bValue2
• ?2
• byte bValue
• int aa 0
• bValue aa 0
• ?3
• float f 0
• f 0.1 0.1

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????UsingMathFunctions????

• Console.WriteLine("Sqrt(2) " Math.Sqrt(2.0))
• Console.WriteLine("PI " Math.PI)
• Console.WriteLine("Sin(PI/6.0) "
  Math.Sin(Math.PI / 6.0))
• Console.WriteLine("Pow(2.0, 0.5) "
  Math.Pow(2.0, 0.5))
• Console.WriteLine("Exp(1) " Math.Exp(1.0))
• Console.WriteLine("ln(e) " Math.Log(Math.E))
• Console.WriteLine("log10(100) "
  Math.Log10(100.0))

26
??

1. ???????
2. ??????
3. ????????????
4. ????
5. ???????
6. ????, ??if??, ?????
7. bool????????
8. ??????

27
????UsingConstant????

• int anInt 123
• const int A_CONST 456
• anInt 321

28
????

• ????
• ????
• ???????

29
??

1. ???????
2. ??????
3. ????????????
4. ????
5. ???????
6. ????, ??if??, ?????
7. bool????????
8. ??????

30
????UsingInDeOperator????

• Console.WriteLine("???????x??")
• int x0 int.Parse(Console.ReadLine())
• Console.WriteLine("???????????add")
• int add int.Parse(Console.ReadLine())
• int x x0
• x x add
• x x0
• x add
• int post
• x x0
• post x
• int pre
• x x0
• pre x

31
???????

• ??? ?-??/-?
• ????--
• ?????(prefix)
• result x
• ?????(postfix)
• result x

32
??

1. ???????
2. ??????
3. ????????????
4. ????
5. ???????
6. ????, ??if??, ?????
7. bool????????
8. ??????

33
??(Relation)???
??? ?? ??? ??
?? ! ???
gt ?? gt ????
lt ?? lt ????
34
if ??
score lt 60
false
true
score 60
35
????UsingSimpleIf????

• Console.Write(
• "???????100??????? ")
• int score int.Parse(Console.ReadLine())
• // ????
• if (score lt 60)
• score 60
• Console.WriteLine("????? " score)

36
if-else ??
score lt 60
true
false
result score
result 60
37
????UsingTerOp????

• Console.Write(
• "???????100??????? ")
• int score int.Parse(Console.ReadLine())
• int result score lt 60 ? 60 score
• // ????
• Console.WriteLine("????? " result)

38
??

1. ???????
2. ??????
3. ????????????
4. ????
5. ???????
6. ????, ??if??, ?????
7. bool????????
8. ??????

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????UsingLB????

• bool x 7 gt 3
• bool y 2 lt 0
• bool xORy x y
• bool xANDy x y
• bool xOy (x y) (x y)
• bool xNy (x y) (x y)

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????

• ????, ????, Debug.Assert()
• x gt 1
• true/false, ???????1 ? 0

41
??????
x y x y x y x y !y
false false false false false true
true false false true true true
false true false true true false
true true true true false false
42
Short-Circuit ????

• ?
• ??
• x y
• x y
• (x y) (x y)
• (x y) (x y)

43
??????

• string first one
• string second One
• string third one
• Console.WriteLine( first second )
• Console.WriteLine( first third )
• Console.WriteLine( first ! second )
• Console.WriteLine( first ! third )

44
??

1. ???????
2. ??????
3. ????????????
4. ????
5. ???????
6. ????, ??if??, ?????
7. bool????????
8. ??????

45
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• ?? ,,/,,,-,,,
• ????????

46
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