??. 217 ????????????? CS217 C programming language

1
??????????????????????????????????
517 101 LAB - 5_2
2
????????????(operator)

• ???????????? (operator) ?????????????????????????
  ??????????????????????????? ??????????????????????
  ?

1. ???????????????????? (assignment operator)
2. ??????????????????? (arithmetic operators)
3. ???????????????????? (bitwise operator)
4. ??????????????????????? (relational operator)
5. ????????????????????? (logical operator)
6. ????????????????? (special operator)

6. ????????????????? (special operator)

3

• ????????????????????????????? ????????
  ??????????????? (operand) ????????????????????????
  ??????????????? 2 ??? ???????????????????????????
  ???????????????????? ????????????????????????????
  ??????????????????????????????

4
???????????????????? (assignment operator)

• ?????????????????????????????????????????
• ?????????????????????????????????????????????????
  ???????????
• ?????? identifier ????????????????????? ???
  expression ?????????????? ??????
  ???????????????????????????????
• ??????????????? ???????? ??????????????????????
• ???? x 50

identifier expression
5
???????? ????????????????????????????????
a 3 x y delta 0.001 sum a b area
length width

• ????????????? ????????????????????? ??????????
  
• ???? int i, j, k,cost,fee
• i j k 100
• cost fee45

6
??????????????????? (arithmetic operators)

• ?????????????????????????????????????????????????
  ??????????

7
???????? ??????????????????????????????????

• 4 3 2
• 4 6
• 9 2 - 15/3 7
• 18 - 5 7
• 13 7
• 20

8
?????????????????????

• -(-5(24-1))((62)58)/4

-(-5(8-1))(858)/4
-(-57)(408)/4
-(2)48/4
-212
10
9
???????????????????????(relational operator)

• ????????????????????????? (condition statement)
  ???? if
• ????????????????????????????
• ?????????????? character string ??????? function
  ?????????string
• ???????????????????????? ?????????????
  (???????????? 0) ???? ???? (???????????? 1
  ????????????????????????? 0)

???????? ???? C ????????????????? boolean (true
???? false) ??????????????? 0 ?????????????
10
????????????????????????????? c
??????????? operator ???????????????????
???? ????????????????????
  ???????????????????????????? printf(value of
true d , 55) / ?? turbo c
????????? 1 / printf(value of false d,
5!5)
11

• lt lt gt gt ??????????????????????????????????
  ????????? ????????????????????????????????????????
  ????? ????????????????????????????????????????????
  ???????
• ! ?????????????????????(equality operator)
  ????????????????????????????????
  ?????????????????????????????????lt lt gt gt
  ???????? ????????????????????????????????????????
  ?????

12
???????? 1

• ????? i, j ???k ??????????????????????????? 1, 2
  ???3
• ???????? ?????????????????????????????????????????
  ???????

13
????????????????????? (logical operator)

• logical operator ??? ????????????????????????????
  ????????????????? ????????????????????? 2
  ???????????????????????? ?????????????????????????
  ??????????? 2 ???? ??? ?????????????????? 1
  ????????????????????? 0 ?????????????????????????
  ??????????(relational operator)
  ???????????????????????? (logical operator)
  ????????

14
????????????????????? (logical operator)
15
??????????????????? operator ???
???????? ?????? operand ??????? 0 ?????? ????
????????????????????? 0 ?????????? ???????? prin
tf(value of (2gt5) (5gt5) d , (2gt5)
(5gt5)) printf(value of (2gt5) (5gt5)
d , (2gt5) (5gt5))
16
????????????????? (special operator)

• ??? ??????????????????????????????????????????????
  ?
• ????? ????????????? ??????????????

• ?????????????????/?? (increment/decrement
  operator)
• ?????????????????????? (pointer-related
  operators)
• ?????????????????? (comma operator)
• ????????????????????? (cast operator)
• ?????????????????? (sizeof operator)

17
?????????????????/?? (increment/decrement
operator)

• ??????????????????????????????????????????????????
  ??????????????

• ????????????????????????????? 2 ?????? ???

18
1. ???????????????? ???? i ???? i--

• ????????????????? operator ???????????
  ????????? ??????????????????????

• ???? count 2
• i count
• ?????????????????????? count ??????????? i ????
• ??????????????????????? count ????????????
• ????? i ???????????? 2
• count ???????????? 3

19
2. ???????????????? ???? i ???? --i

• ?????????????????????????????????????????
  ????????? operator ???????

• ???? count 2
• i count
• ????????????????????????? count ????????????
  ??????????????
• ????????? i
• ????? i ???????????? 3
• count ???????????? 3

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  ?????????????????? (comma
operators)

• ??????????????????? ????? statement ????????
• ???????????? int i 5, j 6 , k

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  ????????????????????? (cast operator)

• ?????????????????????????????????????????????????
  ??????????????????????????????????
  ?????????????????????????
• ????????????????????????????????????????????????
  ??????????? ???
• ???????? type ????????????????????????????????????
  ????? expression ????????????????? ????
  expression ????????????????????????

(type) expression
22

• float cost3.5
• int mycost cost / mycost ???????????? 3
  /
• ??????? ???? c ????????????????????????????????
  ??
• ??????????????????????????????????????????????????
  ??????
• casting operator ????
• i (int) 3.4 6
• i (int) (3.46)

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Compound assignments

• ????????????????????????????????????????
  ?????????????????????
• ???????????? ????
• ??????????????????? C ???????????? operator
  ?????????????????? ??????????? compound
  assignments ?????????????????????????????????????
  ?? operator ?????????? compound assignment
  ??????????

int i 5 i i 5 / i ??????? 10 /
??? ???????????????????????? i ??????? 5
????????????????????????????????? i ????????
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??????????????????? compound assignments
25
???? ????????????????? operator
?????????????????
??????????????????