C exercises

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C exercises
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Recursive programming

• Recursive algorithms are very common in many
  computations like
• series expansion
• tree (directory) navigation
• search, sort etc (divide and conquer)
• integer arithmetic

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Factorials
Base case known solution
double fact(int n) if (nlt1) return 1.
else return double(n)fact(n-1)
Recursive call progress toward base case proof
by induction
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Other Recursive algorithms

• Greatest Common Divisor
• gcd(A,B)gcd(A-B,B) gcd(B,A mod B)
• Zero of a function (bisection algorithm)
• search in ordered collections (binary search)
• operations on compound objects
• print an integer in base N
• void pi(int n, int b) if(ngtb) pi(n/b,b) cout
  ltltnb

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HelloWorld

• Print sin(x) xminltxltxmax
• print first 10 factorials
• do the running sum of the first 1000 integers and
  print it each 20
• find the zero of a function in an interval using
  a bisection algorithm
• find clusters above noise in a linear input

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Chronometer

• A class which display the elapsed time
• implement correctly the functions of the two
  buttons
• (re)-start
• stop
• reset
• lap (read elapsed time without stopping watch)

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Statistical bin

• Return sum, average and rms of the inputs
• implement operations among bins with correct
  error propagation

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Multiplexer

• A system which switches among different
  algorithms depending on some predefined input
• to be written without a single switch or if
  statement

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Histograms

• Book, fill, print 1d,2d hist
• operate on them
• name them

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CLHEP

• Use vectors
• use rotations
• use Lorenz-Vectors
• Jet algorithm

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Estrazioni del lotto

• Extract 5 out of 90 numbers

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Tombola

• Full Tombola including extraction and card checks

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Shapes
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Shapes and visitors

• Area an perimeters
• Sort shapes by area

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Daq hardware