"error: expected primary-expression before '<' token." What am I missing? : <p>I've done a very similar code in C without such errors.</p>

<p>I'm assuming that I got all the header files I need?    </p>

<pre><code>#include &lt;iostream&gt;
#include &lt;cmath&gt;
#include &lt;string&gt;
using namespace std;
int main(){    
double percentage;
cout &lt;&lt; "enter percentage" &lt;&lt; endl;
cin &gt;&gt; percentage;
string letter;
        if (percentage &gt;= 98)
        letter = "A+";
</code></pre>

<p>This is where the error starts to appear on every condition line. I deleted the rest of the grades in this sample to avoid redundancy. </p>

<pre><code>else if (percentage &gt;= 92 &amp;&amp; &lt; 98) //"error: expected primary-expression before '&lt;' token."
{
        letter = "A";
}
else if (percentage &gt;= 90 &amp;&amp; &lt; 92) //"error: expected primary-expression before '&lt;' token."
{
        letter = "A-";
}
else if (percentage &gt;= 88 &amp;&amp; &lt; 90) //"error: expected primary-expression before '&lt;' token."
{
        letter = "B+";
}
</code></pre>

<p>This is where it stops</p>

<pre><code>else {letter = "F";}
cout &lt;&lt; "Grade: " &lt;&lt; letter &lt;&lt; endl;

return 0;
}
</code></pre>
