Extract substring from the first letter : <p>I need to extract substring from string but starting with the first letter</p>

<p><strong>example</strong> : </p>

<pre><code>string s1 = "12 x 13 ABC 12@ 15.8" substring =  ABC 12@ 15.8
string s2 = "25 x 32 FER @23.8" substring =  FER @23.8
</code></pre>

<p>I tried the index of for the letter A or F but it didn't work</p>

<p>thanks</p>
