Computer Programming Lab 11 Solution

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Computer ProgrammingLab 11 Solution

• Shyh-Kang Jeng
• Department of Electrical Engineering/
• Graduate Institute of Communication Engineering
• National Taiwan University

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Lab Exercise 10 Tortoise and the Hare (1/6)

• In this problem you will recreate the classic
  race between the tortoise and the hare. You will
  use random number generation to develop a
  simulation of this memorable event.
• Our contenders begin the race at square 1 of
  70 squares. Each square represents a possible
  position along the race course. The finish line
  is at square 70.

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Lab Exercise 10 Tortoise and the Hare (2/6)

• There is a clock that ticks once per second.
  With each tick of the clock, your program should
  adjust the position of the animals according to
  the following rules

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Lab Exercise 10 Tortoise and the Hare (3/6)
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Lab Exercise 10 Tortoise and the Hare (4/6)

• Begin the race by printing
• BANG ! ! ! ! !
• AND THEYRE OFF ! ! ! ! !
• Start each animal at position 1 (i.e., the
  starting gate). If an animal slips left before
  square 1, move the animal back to square 1. For
  each tick of the clock (i.e., each repetition of
  a loop), print a 70-position line showing the
  letter T in the Tortoises position and the
  letter H in the hares position. Occasionally,
  the contenders will land on the same square.

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Lab Exercise 10 Tortoise and the Hare (5/6)

• In this case, the tortoise bites the hare, and
  your program should print OUCH! ! ! beginning at
  that position. All print positions other than
  the T, the H or the OUCH! ! ! should be blank.
• After printing each line, determine whether
  either animal has reached or passes square 70.
  If so, print the name of the winner, and
  terminate the simulation. If the tortoise wins,
  print TORTOISE WINS! ! ! YAY! ! !

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Lab Exercise 10 Tortoise and the Hare (6/6)

• If the hare wins, print Hare wins, Yuch. . If
  neither animal wins, perform the loop again to
  simulate the next tick of the clock.
• In this program, you will be passing arguments
  via call by reference, using reference notation.
  After successfully completing the exercise,
  rewrite your solution to use pointer notation.

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Sample Output
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Solution (1/6)

• // CPLab11\Main.cpp
• include ltiostreamgt
• using stdcout
• using stdendl
• include ltcstdlibgt
• include ltctimegt
• include ltiomanipgt
• using stdsetw
• const int RACE_END 70
• void moveTortoise( int turtlePtr )
• void moveHare( int bunnyPtr )
• void printCurrentPositions( int turtlePtr, int
  bunnyPtr )

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Solutio (2/6)

• int main()
• int tortoise 1
• int hare 1
• int timer 0
• srand( time( 0 ) )
• cout ltlt "ON YOUR MARK, GET SET\nBANG
  !!!!"
• ltlt "\nAND THEY'RE OFF !!!!\n"
• // control race
• while ( tortoise ! RACE_END hare ! RACE_END
  )
• moveTortoise( tortoise )
• moveHare( hare )
• printCurrentPositions( tortoise, hare )
• timer
• // end while

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Solution (3/6)

• if ( tortoise gt hare )
• cout ltlt "\nTORTOISE WINS!!! YAY!!!\n"
• else
• cout ltlt "Hare wins. Yuch.\n"
• cout ltlt "TIME ELAPSED " ltlt timer ltlt " seconds"
  
• ltlt endl
• return 0
• // end main

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Solution (4/6)

• // move tortoise
• void moveTortoise( int turtlePtr )
• int x 1 rand() 10
• // determine which move to make
• if ( x gt 1 x lt 5 ) // fast plod
• turtlePtr 3
• else if ( x 6 x 7 ) // slip
• turtlePtr - 6
• else // slow plod
• ( turtlePtr )
• // ensure that tortoise remains within subscript
  range
• if ( turtlePtr lt 1 )
• turtlePtr 1
• else if ( turtlePtr gt RACE_END )
• turtlePtr RACE_END
• // end moveTortoise

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Template (5/6)

• // move hare
• void moveHare( int bunnyPtr )
• int y 1 rand() 10
• if ( y 1 y 2 ) // big hop
• bunnyPtr 9
• else if ( y 3 ) // big slip
• bunnyPtr - 12
• else if ( y gt 4 y lt 6 ) // small hop
• bunnyPtr 1
• else if ( y 7 y 8 ) // small slip
• bunnyPtr - 2
• else // sleep
• return

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Solution (6/6)

• if ( bunnyPtr lt 1 )
• bunnyPtr 1
• else if ( bunnyPtr gt RACE_END )
• bunnyPtr RACE_END
• // end moveHare
• // output positions of animals
• void printCurrentPositions( int snapperPtr, int
  bunnyPtr )
• if ( bunnyPtr snapperPtr )
• cout ltlt setw( bunnyPtr ) ltlt "OUCH!!!"
• else if ( bunnyPtr lt snapperPtr )
• cout ltlt setw( bunnyPtr ) ltlt "H"
• ltlt setw( snapperPtr - bunnyPtr ) ltlt "T"
• else
• cout ltlt setw( snapperPtr ) ltlt "T"
• ltlt setw( bunnyPtr - snapperPtr ) ltlt "H"
• cout ltlt "\n"
• // end printCurrentPositions

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Solution (1/6)

• // CPLab11\Main.cpp
• include ltiostreamgt
• using stdcout
• using stdendl
• include ltcstdlibgt
• include ltctimegt
• include ltiomanipgt
• using stdsetw
• const int RACE_END 70
• void moveTortoise( int turtlePtr )
• void moveHare( int bunnyPtr )
• void printCurrentPositions( int turtlePtr, int
  bunnyPtr )

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Solution (2/6)

• int main()
• int tortoise 1
• int hare 1
• int timer 0
• srand( time( 0 ) )
• cout ltlt "ON YOUR MARK, GET SET\nBANG
  !!!!"
• ltlt "\nAND THEY'RE OFF !!!!\n"
• // control race
• while ( tortoise ! RACE_END hare ! RACE_END
  )
• moveTortoise( tortoise )
• moveHare( hare )
• printCurrentPositions( tortoise, hare )
• timer
• // end while

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Solution (3/6)

• if ( tortoise gt hare )
• cout ltlt "\nTORTOISE WINS!!! YAY!!!\n"
• else
• cout ltlt "Hare wins. Yuch.\n"
• cout ltlt "TIME ELAPSED " ltlt timer ltlt " seconds"
  ltlt endl
• return 0
• // end main

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Solution (4/6)

• // move tortoise
• void moveTortoise( int turtlePtr )
• int x 1 rand() 10
• // determine which move to make
• if ( x gt 1 x lt 5 ) // fast plod
• turtlePtr 3
• else if ( x 6 x 7 ) // slip
• turtlePtr - 6
• else // slow plod
• ( turtlePtr )
• // ensure that tortoise remains within subscript
  // range
• if ( turtlePtr lt 1 )
• turtlePtr 1
• else if ( turtlePtr gt RACE_END )
• turtlePtr RACE_END
• // end moveTortoise

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Solution (5/6)

• // move hare
• void moveHare( int bunnyPtr )
• int y 1 rand() 10
• if ( y 1 y 2 ) // big hop
• bunnyPtr 9
• else if ( y 3 ) // big slip
• bunnyPtr - 12
• else if ( y gt 4 y lt 6 ) // small hop
• bunnyPtr 1
• else if ( y 7 y 8 ) // small slip
• bunnyPtr - 2
• else // sleep
• return

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Solution (6/6)

• if ( bunnyPtr lt 1 )
• bunnyPtr 1
• else if ( bunnyPtr gt RACE_END )
• bunnyPtr RACE_END
• // end moveHare
• // output positions of animals
• void printCurrentPositions( int snapperPtr, int
  bunnyPtr )
• if ( bunnyPtr snapperPtr )
• cout ltlt setw( bunnyPtr ) ltlt "OUCH!!!"
• else if ( bunnyPtr lt snapperPtr )
• cout ltlt setw( bunnyPtr ) ltlt "H"
• ltlt setw( snapperPtr - bunnyPtr ) ltlt "T"
• else
• cout ltlt setw( snapperPtr ) ltlt "T"
• ltlt setw( bunnyPtr - snapperPtr ) ltlt "H"
• cout ltlt "\n"
• // end printCurrentPositions