cpp/cs104/exceptions/divide

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Description
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An exception can be caught by one function which can check if it can do anything about the problem and if not, it can re-throw the exception by simply writing:
<pre>
throw;
</pre>
in a <tt>catch</tt> block.
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shown when solved

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Copied from problem cpp/cs104/exceptions/divide_std_except (author: redekopp@usc.edu)
Copied from problem cpp/cs104/exceptions/divide_throw_catch_main (author: redekopp@usc.edu)
Copied from problem cpp/cs104/exceptions/divide_throw_catch_primitive (author: redekopp@usc.edu)
Copied from problem cpp/cs104/exceptions/divide_throw_only (author: redekopp@usc.edu)
Copied from problem cpp/cs104/exceptions/divide_assert (author: redekopp@usc.edu)
Copied from problem cpp/cs104/exceptions/divide1 (author: redekopp@usc.edu)

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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 <string>
#include <stdexcept>
using namespace std;
int divide(int num, int denom)
{
if(denom == 0){
throw std::invalid_argument("Denom is 0");
}
cout << "Normal case" << endl;
return(num/denom);
}
int f1(int x)
{
try {
return divide(x, x-2);
}
catch(std::invalid_argument& e){
// assume code that checks if it can do anything
cout << "Oops, I'm not the root cause." << endl;
cout << "Let's throw it up the stack again" << endl;
throw; // throw's e again
}
}

int main()
{
int res = -1, a;
cout << "Enter: " << endl;
cin >> a;

while(true){
try {
res = f1(a);
// I'll only get here if no exception occurred
break;
}
catch(std::invalid_argument& e ){
cout << e.what() << endl;
cout << "\nTrying again" << endl;
cin >> a;
}
}
cout << res << 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 [{}]

[{"stdin":"2 4"} ]
C++ test suite
See manual

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Property	Value
Description html markup shown to student	An exception can be caught by one function which can check if it can do anything about the problem and if not, it can re-throw the exception by simply writing: <pre> throw; </pre> in a <tt>catch</tt> block.
Epilogue html markup shown when solved	remove
Public permissions	remove
Remarks Comments, history, license, etc.	Copied from problem cpp/cs104/exceptions/divide_std_except (author: redekopp@usc.edu) Copied from problem cpp/cs104/exceptions/divide_throw_catch_main (author: redekopp@usc.edu) Copied from problem cpp/cs104/exceptions/divide_throw_catch_primitive (author: redekopp@usc.edu) Copied from problem cpp/cs104/exceptions/divide_throw_only (author: redekopp@usc.edu) Copied from problem cpp/cs104/exceptions/divide_assert (author: redekopp@usc.edu) Copied from problem cpp/cs104/exceptions/divide1 (author: redekopp@usc.edu) 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 <string> #include <stdexcept> using namespace std; int divide(int num, int denom) { if(denom == 0){ throw std::invalid_argument("Denom is 0"); } cout << "Normal case" << endl; return(num/denom); } int f1(int x) { try { return divide(x, x-2); } catch(std::invalid_argument& e){ // assume code that checks if it can do anything cout << "Oops, I'm not the root cause." << endl; cout << "Let's throw it up the stack again" << endl; throw; // throw's e again } } int main() { int res = -1, a; cout << "Enter: " << endl; cin >> a; while(true){ try { res = f1(a); // I'll only get here if no exception occurred break; } catch(std::invalid_argument& e ){ cout << e.what() << endl; cout << "\nTrying again" << endl; cin >> a; } } cout << res << 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 `[{}]`	[{"stdin":"2 4"} ]
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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