whats wrong with this program
<pre><code>#include &lt;iostream&gt; 
using namespace std;

int main () 
{
    double testscore;
    cout &lt;&lt; " Enter your test score and i will tell you the letter grade you earned ";
    cin &gt;&gt; testscore;
    switch (testscore)
    {
        case (testscore &lt; 60.0):
            cout &lt;&lt; "your grade is F.\n";
            break;
        default:
            cout &lt;&lt; "that score isnt valid\n.";
    }
return 0;
}
</code></pre>
