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logic error
hey guys...i have problem with this coding here..
#include <iostream>
using namespace std;
int main()
{
int found=0,count=5;
{
if(!found||--count==0)
cout<<"danger"<<endl;
cout<<"count="<<count<<endl;
}
system ("PAUSE");
return 0;
}
the discussion goes like this...my friend said that the output should be:
danger
count=4...but
it went like this,
danger
count=5
any idea?
#include <iostream>
using namespace std;
int main()
{
int found=0,count=5;
{
if(!found||--count==0)
cout<<"danger"<<endl;
cout<<"count="<<count<<endl;
}
system ("PAUSE");
return 0;
}
the discussion goes like this...my friend said that the output should be:
danger
count=4...but
it went like this,
danger
count=5
any idea?
Simple: what is
Check if (!found) or (--code) is true.
(!found) is true, so there is no need to check for (--code), and so it will never get executed, unless (found) isn't 0.
It's c++'s default optimization.
If you reverse them into
if(!found || --code) supposed to do?Check if (!found) or (--code) is true.
(!found) is true, so there is no need to check for (--code), and so it will never get executed, unless (found) isn't 0.
It's c++'s default optimization.
If you reverse them into
if(--code || !found) (--code) will be executed, and the result will be the one you expected.
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