How convert javascript to jquery

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Javascript

Java

jQuery

i don't know how to convert like 

getElementById

 document.getElementById("cnt").innerHTML += "select: " +numberOfAttribute+". By javascript<br>";

function javascript_click() {
if (document.getElementById("value3").value && document.getElementById("value4").value ) {
var attName=document.getElementById("value3").value;
var attValue=document.getElementById("value4").value;
var total_name_and_value = "[" + attName + "=" + attValue + "]";
var numberOfAttribute = document.querySelectorAll(total_name_and_value).length;
document.getElementById("cnt").innerHTML += "select: " +numberOfAttribute+". By javascript
";
}

if(document.getElementById("value1").value=='' && document.getElementById("value2").value=='' && document.getElementById("value3").value=='' && document.getElementById("value4").value=='')
{
document.getElementById("cnt").innerHTML += "wrong.
";
}
}

What I have tried:

$("value3").value;

i tried like this and it didn't work..