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Assume the process function uses a "resource" to do its job.
 
Thus during execution the number of resources should be reduced by 1 and then restored upon completion of the <tt>process</tt> function.
 
The solution seems simple but what if <tt>f1</tt> throws an exception?? 
You could put the call to f1 in a <tt>try</tt> block and then add <tt>catch</tt> a catch block to restore the value, and then rethrow.
But there is a better way. See exercise <tt>raii2</tt> for a solution to this problem.

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Copied from problem cpp/cs104/cpp11/sharedptr1 (author: redekopp@usc.edu)

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

Correct answer
Template / Reference solution

Template / Reference solution

#include <string>
#include <stdexcept>
#include <iostream>

using namespace std;

int numResources = 2;

void f1(int x)
{
// Perform some processing but may throw an exception
\hide[
if(x > 0) throw invalid_argument("bad");
else if(x < 0) throw logic_error("really bad");
else cout << "Normal" << endl;
]\
}

// Should decrement numResources during execution
void process(int a)
{
// Assume that to process, this function "uses" a resources
// Thus it should decrement the number of resources
// and then restore it back at the end of the function
\[ REDACTED ]\
cout << "in useResourceToProcess(): numResources = " << numResources << endl;

// Do the work
\[
REDACTED
\show:
f1(a);
]\
// restore the number of resources
\[ REDACTED ]\
}

int main()
{
try {
int a; cin >> a;
process(a);
}
catch(exception& e){
cout << "Exception: " << e.what() << endl;
}
cout << "back in main(): numResources = " << numResources << 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":"0"},{"stdin":"1"},{"stdin":"-1"}]
C++ test suite
See manual

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["-std=c++11"]
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json list of flags
see default_cppflags
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Property	Value
Description html markup shown to student	Assume the process function uses a "resource" to do its job. <br><br> Thus during execution the number of resources should be reduced by 1 and then restored upon completion of the <tt>process</tt> function. <br><br> The solution seems simple but what if <tt>f1</tt> throws an exception?? <br> You could put the call to f1 in a <tt>try</tt> block and then add <tt>catch</tt> a catch block to restore the value, and then rethrow. <strong>But there is a better way. See exercise <tt>raii2</tt> for a solution to this problem.</strong>
Epilogue html markup shown when solved	remove
Public permissions	remove
Remarks Comments, history, license, etc.	Copied from problem cpp/cs104/cpp11/sharedptr1 (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 <string> #include <stdexcept> #include <iostream> using namespace std; int numResources = 2; void f1(int x) { // Perform some processing but may throw an exception \hide[ if(x > 0) throw invalid_argument("bad"); else if(x < 0) throw logic_error("really bad"); else cout << "Normal" << endl; ]\ } // Should decrement numResources during execution void process(int a) { // Assume that to process, this function "uses" a resources // Thus it should decrement the number of resources // and then restore it back at the end of the function \[ REDACTED ]\ cout << "in useResourceToProcess(): numResources = " << numResources << endl; // Do the work \[ REDACTED \show: f1(a); ]\ // restore the number of resources \[ REDACTED ]\ } int main() { try { int a; cin >> a; process(a); } catch(exception& e){ cout << "Exception: " << e.what() << endl; } cout << "back in main(): numResources = " << numResources << 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":"0"},{"stdin":"1"},{"stdin":"-1"}]
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"]`	["-std=c++11"] remove
Remove default compiler flag(s) json list of flags see default_cppflags e.g. `["-Wno-write-strings"]`	remove

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