triangle

index.html
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<!doctype html>
<html>

    <head>

        <script src="javascript.js"></script>


    </head>

    <body>


    </body>

</html>
--------------------------------


javascript.js
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var st = "";
var num = prompt("enter a whole number");


for(var i=1; i<=num; i+=1){

    for(var j=0; j<num-i; j+=1){
        st+="&nbsp;&nbsp;";
    }

    for(var k=0; k<2*i-1; k+=1){
        st+="*";
    }

    st+="<br/>";

}

document.write(st);
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