?a???s?as? t?? PowerPoint

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Templates Standard Template Library (STL) Excep
tions
?etapt???a?? ?????aµµa Sp??d??, ?µ?µa
?fa?µ?sµ???? ?????f??????
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Templates

• ?a p??t?pa (templates) e??a? µ?a ap? t?? p????
  ?s????? d??at?t?te? t?? C (Bjarne Stroustrup,
  1988)
• ?a templates µa? ep?t??p??? ?a ?a????s??µe, µ?sa
  se ??a µ??ad??? tµ?µa ??d??a, ??a s?????
  s?s?et???µe??? s??a?t?se?? (template functions)
• ?p????µe ??a pa??de??µa ?a ??????µe ??a µ??ad???
  p??t?p? s????t?s?? ??a µ?a s????t?s? ta????µ?s??
  e??? p??a?a ?a? st? s????e?a ?a af?s??µe st? C
  ?a pa???e? ?e????st?? s??a?t?se?? ??a t??
  ta????µ?s? e??? p??a?a a?e?a???, p??a?a a???µ??
  ????t?? ?p?d?ast????, p??a?a a?fa???µ?t???? ??p
• ?p?p???? µp????µe ?a ???s??µe p??t?pa ???se??
  (class templates)
• ???????a function templates ? (pa??????)
  template functions
• class templates ? (pa??????) template
  classes

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Templates

• ?st? µ?a s????t?s? printArray(int T, int size)
• ?? ?????µe ?a e?t?p?s??µe ??a? p??a?a µe
  st???e?a p?? e??a? a???µ?? ????t?? ?p?d?ast????,
  p??pe? ?a "?pe?f??t?s??µe" t? ???µa printArray
  printArray(double T, int size)
• ?pe?f??t?µ??e? s??a?t?se?? ???s?µ?p?????ta? ??a
  t?? e?t??es? pa??µ???? ?e?t??????? se
  d?af??et????? t?p??? ded?µ????
• ?? ?? ?e?t?????e? e??a? pa??µ???t?pe? ??a ???e
  t?p?, e??a? ?ata?????te?? ? ???s? p??t?p??
  s??a?t?se??
• ? p????aµµat?st?? ???fe? ??a µ??ad??? p??t?p?
  s????t?s??
• ??se? t?? t?p?? t?? ???sµ?t??, ? µeta???tt?st??
  pa???e? ?e????st?? s??a?t?se?? a?t??e?µe???
  ??d??a ??a t? ?e???sµ? ???e ???s??

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Function Templates

• ??a ta p??t?pa s??a?t?se?? ?e?????? µe t?
  desµe?µ??? ???? template a????????µe?? ap? µ?a
  ??sta pa?aµ?t??? µ?sa se lt gt
• Se ???e pa??µet?? p??pe? ?a p????e?ta? e?te ?
  desµe?µ??? ???? class e?te ? typename p.?.
  

template ltclass Tgt T maximum( T value1, T value2,
T value3) T max value1 if(value2 gt max)
max value2 if(value3 gt max) max
value3 return max
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Class Templates

• St??ßa (stack) ??µ? ded?µ???? ?p?? ta ded?µ??a
  e?s????ta? p??t?te ?at? t?? ?d?a se??? ?a?
  a?a?t???ta? µe se??? LIFO
• ? ???p???s? µ?a? st??ßa? e?a?t?ta? ap? t?? t?p?
  t?? ded?µ????
• ?pa?a???s?µ?p???s? ???sµ?? t?? ?e????? ?????a?
  µ?a? st??ßa? µe p??t?pa ???se??

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Class Templates
template ltclass Tgt class Stack public
Stack(int s) bool push(T) T
pop() private int size int top T
stackPtr bool isEmpty() return top -1
bool isFull() return top size-1
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Class Templates
template ltclass Tgt Stacklt T gtStack(int s)
size s gt 0 ? s 10 top -1 stackPtr
new Tsize template ltclass Tgt bool
StackltTgtpush(T pushValue) if(!isFull())
stackPtrtop pushValue return
true else return false
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Class Templates
template ltclass Tgt T StackltTgtpop() if(!isEmpt
y()) return stackPtrtop-- else cout ltlt
"Nothing to retrieve" ltlt endl
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STL

• ? C pe???aµß??e? t?? p??t?p? ß?ß??????? STL µe
  ????? s??p? ?a d?e??????e? t?? epa?a???s?µ?p???s?
  ??d??a
• Alexander Stepanov, Meng Lee (Hewlett Packard
  generic programming a?e?a?t?s?a d?µ?? e??????
  ap? ?p??e?µe?a data)
• ????? t?? p??t?p?? C
• ????a s?stat???
• ?p?d??e?? (containers)
• epa?a??pte? (iterators)
• a??????µ?? (algorithms)
• ? ß?ß??????? STL e??a? p??? µe???? !!
• ????t?? ? d?µ??????a p??t?p?? d?µ?? ded?µ????
  p?? ?a ?e?t??????? e????a µe ???a p?????µµata

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STL

• St?? C/C ? p??sßas? sta st???e?a µ?a? d?µ??
  (p.?. p??a?a) ???eta? µe t? ???s? pointers
• St?? STL ? p??sßas? st??? ?p?d??e?? ???eta? µ?s?
  epa?a??pt??
• ?d?a "a?s??s?" µe t??? de??te?
• "e??p??te??" s?µpe??f???
• ??? ?? ?p?d??e?? e?s?µat????? st???e??de??
  ?e?t?????e?, p?? e?e??t?µ???? a??????µ??
  ???p?????ta? ?e????st?
• H STL ap?fe??e? t? ???s? t?? new ?a? delete a???
  ???s?µ?p??e? ?ata?eµ?t?? (allocators) µ??µ??

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Containers

• ?a?ade??µata
• vector - ta?e?a p??s???? ?a? d?a??af? st? t????
• - ?µes? p??ßas? se ???e st???e??
• list - d?p?? s??dedeµ??? ??sta, ta?e?a p??s????
  ?a? d?a??af? ?p??d?p?te
• set - ta?e?a e??es?, de? ep?t??p??ta? d?p???
  ?ata????se??
• multiset - ta?e?a e??es?, ep?t??p??ta? d?p???
  ?ata????se??
• stack - last-in-first-out (LIFO)
• queue - first-in-first-out (FIFO)

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Containers

• ?p?????? p????? ?e?t?????e? p?? efa?µ????ta? se
  p?????? ?p?d??e??
• empty - ep?st??fe? true a? de? ?p?????? st???e?a
• size - ep?st??fe? t?? t?????ta a???µ? t??
  st???e???
• swap - e?a??a?? t?? ??s?? d?? st???e???
• begin - ep?st??fe? epa?a??pt? p??? t? p??t?
  st???e??
• erase - d?a??af? e??? ? pe??ss?t???? st???e???
• operator - ????es? e??? ?p?d???a se ??a? ????
• operator lt - ?p?st??fe? true a? ??a? ?p?d???a?
  e??a? µ????te??? ap? ??a? ????

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Iterators

• ?a???? p?? ?? epa?a??pte? e??a? ???p???µ????
  a?????a µe t? d?µ? p??? t?? ?p??a "de??????",
  µ???????ta? ???sµ??e? ?????? ?e?t?????e?
• - te?est?? ?µµes?? a?af????
• - µeta????s? t?? epa?a??pt? st? ep?µe??
  st???e??
• ???s?µ?p????µe ??a a?t??e?µe?? iterator ??a ?a
  a?afe????µe se st???e?a ta ?p??a µp????? ?a
  t??p?p???????.
• ???s?µ?p????µe ??a a?t??e?µe?? const_iterator ??a
  ?a a?afe????µe se st???e?a ta ?p??a de? µp?????
  ?a t??p?p???????

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Vectors

• ??a d?µ? vector e??a? ??a? "e??p??te???" p??a?a?
  (s??e?e?? ??se?? µ??µ??)
• t? µ??e??? µp??e? ?a a????e? d??aµ???
• ??a vector µp??e? ?a a?ate?e? se ??a ????
• ? p??s???? st???e??? st? t???? e??a? ap?d?t???
• ? p??s???? st???e??? st? µ?s? e??a? ?p?????st???
  dapa????
• ?a st???e?a µp????? ?a p??spe?ast??? µ?s? t??
  ?pe?f??t?µ???? te?est?

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Algorithms

• ????? t?? STL ?? ß?ß??????e? ???se?? µeta??
  d?af???? ?atas?e?ast?? ?ta? as?µßate?
• ?????? ???s?µ?p????sa? ???????µ???t?ta ?a?
  p???µ??f?sµ? µe t? s?et??? ??st?? ta??t?ta? t??
  virtual s??a?t?se??
• ?? a??????µ?? ?ta? e?s?µat?µ???? st?? d?µ??
• St?? STL ?p?d??e?? ?a? a??????µ?? d?a???????ta?
• ?a??de??µa ???s? ßas???? a??????µ?? ta????µ?s??

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?e???sµ?? ??a???se??

• ?st? ?t? ??a? p????aµµat?st?? ???e? ??p???
  sf??µa, ?p?? t? ?a ??t?se? ??a st???e?? µet? t?
  t???? e??? d?a??sµat?? se µ?a ???s?
• ? s????af?a? t?? ???s?? ??e? t?? e???
  d??at?t?te?
• ?a µ?? e????e? t? s?????? t?? sf??µat?? ?a? ?a
  e?te??se? t?? ??d??a (p??a??? µe s?ßa???
  s???pe?e?)
• ?a e????e? t? s?????? t?? sf??µat?? ?a? ?a µ??
  ???e? t?p?ta a? s?µße?
• ?a e????e? t? s?????? t?? sf??µat?? ?a? ?a
  e??µe??se? t? ?a??? p????aµµa (µ???d?) a? s?µße?
• double future_val(double amount, double p, int n)
• return amount pow(1 p / 100, n)

?? ????e? ?? future_val(1000, -100, -1) ??
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?e???sµ?? ??a???se??

• ???a? d??at?? ?a ???p????e? ??d??a? e??????

double future_val(double amount, double p, int
n) if (p lt 0 n lt 0) return 0 return
amount pow(1 p / 100, n)

• ?? ?a??? p????aµµa de? e??µe???eta? ??t? ??a t?
  ?????. ?? e???ße? t? 0 ?? ?a?????? t?µ? ?a?
  s??e??se? µp??e? ?a p????????? pe?a?t???
  p??ß??µata

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?e???sµ?? ??a???se??

• ? C d?a??te? ??a µ??a??sµ? e?d?p???s??, p??
  ?a?e?ta? ?e???sµ?? e?a???se?? (exception
  handling)
• ?ta? µ?a s????t?s? e?t?p??e? ??a sf??µa,
  p???a?e? µ?a e?a??es? (throws an exception)

double future_val(double amount, double p, int
n) if (p lt 0 n lt 0) logic_error
description("illegal parameter") throw
description return amount pow(1 p /
100, n)
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?e???sµ?? ??a???se??

• ? desµe?µ??? ???? throw ?p?d????e? t?? ???d? ap?
  t? s????t?s?
• Ost?s?, ? s????t?s? de? ep?st??fe? ?p???e?t???
  st?? ?a???sa
• ?????e? t?? ?a???sa s????t?s?, a?t? p?? t??
  ???ese ?.?.?. µ????? ?t?? ß?e?e? ??a? ?at???????
  ?e???st?? (handler)

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?e???sµ?? ??a???se??

• ?a???ete ??a? ?e???st? e?a???se?? µe t??
  a??????? ??d??a

try code catch (logic_error e)
handler