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Description
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We want to write a program that simulates the roll of two individual
6-sided dice (fair dice with equal probability of landing on 1-6). We
want to declare the variables d1 and d2 in main() but set their values
via the help of two other functions: <tt>roll_one()</tt> and
<tt>roll_two()</tt>.
<ul>
<li>
<tt>roll_one()</tt> should set the value of only one die at a time.
<li>
<tt>roll_two()</tt> should take both die and call <tt>roll_one()</tt> once for each
die value.
</ul>

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Comments, history, license, etc.

Originally by Mark Redekopp (redekopp@usc.edu) and Dave Pritchard (daveagp@gmail.com)

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Engine
Choices
json list of string, bool pairs
e.g. [["good", true], ["bad", false]]

Correct answer
Template / Reference solution

Template / Reference solution

#include <iostream>
#include <cstdlib>
using namespace std;

// Takes pointer to integer and changes the pointed-at value
// to be a random number between 1 and 6
void roll_one(\[int*]\ die) {
\[ *die ]\ = 1 + rand()%6;
}

// Takes two pointers to integers and changes the pointed-at values
// to be random numbers between 1 and 6
void roll_two(\[int*]\ die1, \[int*]\ die2) {
// Call the roll_one() function twice to set die1 & die2
\[
roll_one(die1);
roll_one(die2);
]\
}

int main() {
int d1=0, d2=0; // two integers representing dice values
cout << "Before: d1 is " << d1 << " and d2 is " << d2 << endl;

srand(0); // not acutally random, to facilitate testing

// We want to change the contents of d1 and d2 in the function
// roll_one(). But we will first pass them through roll_two()
// which will call roll_one() twice...once for each die

// Pass appropriate values for d1 and d2 as the arguments
roll_two(\[&d1, &d2]\);

// d1 and d2 should be changed by the previous call to roll_two()
// so let's check their value.
cout << "After: d1 is " << d1 << " and d2 is " << d2 << endl;
return 0;
}

Java test suite
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C++ test suite
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e.g. [{"stdin":"hi", "args":["4", "5"]}, {"stdin":"noargs"}]
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[
{}
]

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Property	Value
Description html markup shown to student	We want to write a program that simulates the roll of two individual 6-sided dice (fair dice with equal probability of landing on 1-6). We want to declare the variables d1 and d2 in main() but set their values via the help of two other functions: <tt>roll_one()</tt> and <tt>roll_two()</tt>. <ul> <li> <tt>roll_one()</tt> should set the value of only one die at a time. <li> <tt>roll_two()</tt> should take both die and call <tt>roll_one()</tt> once for each die value. </ul>
Epilogue html markup shown when solved	remove
Public permissions	remove
Remarks Comments, history, license, etc.	Originally by Mark Redekopp (redekopp@usc.edu) and Dave Pritchard (daveagp@gmail.com) remove
Engine
Choices json list of string, bool pairs e.g. `[["good", true], ["bad", false]]`
Correct answer
Template / Reference solution
Template / Reference solution	#include <iostream> #include <cstdlib> using namespace std; // Takes pointer to integer and changes the pointed-at value // to be a random number between 1 and 6 void roll_one(\[int]\ die) { \[ die ]\ = 1 + rand()%6; } // Takes two pointers to integers and changes the pointed-at values // to be random numbers between 1 and 6 void roll_two(\[int]\ die1, \[int]\ die2) { // Call the roll_one() function twice to set die1 & die2 \[ roll_one(die1); roll_one(die2); ]\ } int main() { int d1=0, d2=0; // two integers representing dice values cout << "Before: d1 is " << d1 << " and d2 is " << d2 << endl; srand(0); // not acutally random, to facilitate testing // We want to change the contents of d1 and d2 in the function // roll_one(). But we will first pass them through roll_two() // which will call roll_one() twice...once for each die // Pass appropriate values for d1 and d2 as the arguments roll_two(\[&d1, &d2]\); // d1 and d2 should be changed by the previous call to roll_two() // so let's check their value. cout << "After: d1 is " << d1 << " and d2 is " << d2 << endl; return 0; }
Java test suite See manual
C++ test suite json list of stdin/args tests e.g. `[{"stdin":"hi", "args":["4", "5"]}, {"stdin":"noargs"}]` to just run once with no input use `[{}]`	[ {} ]
C++ test suite See manual
Forbidden substrings json list of strings e.g. `["for","while"]`	remove
Solution visibility	remove
Java imports json list of importables e.g. `["java.util.*"]`	remove
Override Java classname else defaults to websheet name	remove
Dependent on other websheets? json list of websheet names in this folder e.g. `["DataStructure"]`	remove
Is example? i.e., just a demo	remove
Add compiler flag(s) json list of flags e.g. `["-Wno-unused-variable"]`	remove
Remove default compiler flag(s) json list of flags see default_cppflags e.g. `["-Wno-write-strings"]`	remove

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