<script>
    var weighttolift = 0;
    var percentage = 0;

    var target = 0;
    // calculation function starts here

    function startcalc() {
        // making variables to use the values later.

        // make the weight that have to be lifted after minus the bar weight etc.

        var weighttolift = jQuery(".input-weight").val();
        var weighttolift = jQuery("input[name=Weight]").val();
        var percentage = jQuery("input[name=Percentage]").val();
        var bar = jQuery(".input-bar").val();

        var bar = jQuery("input[name=Bar]").val();

        // targeted values
        var target = ("input[name=Target]").val();

        // this funciton calculates the weight percentage , final , difference etc

        targets = Math.floor(weighttolift * percentage);

        // final wieght calculater
        target.value = targets;

        var finals = Math.floor(parseInt(target.value) - parseInt(bar));


        //this function assign the required plate pairs value 

        var weightcalculate = 0;

        var avail45 = document.getElementById('avail45').value;

        if (avail45 == 0) {
            document.getElementById('req45').value = null;

        } else {
            //counts the required plates
            var c = 0;
            for (var a = 1; a <= avail45; a++) {
                if (finals >= 90) {
                    c++;
                    finals -= 90;
                    weightcalculate += 90;
                }

            }
            if (c == 0) {
                document.getElementById('req45').value = null;
            } else {
                document.getElementById('req45').value = c;
            }

        }

        var avail35 = document.getElementById('avail35').value;

        if (avail35 == 0) {
            document.getElementById('req35').value = null;

        } else {
            //counts the required plates
            var d = 0;
            for (var a = 1; a <= avail35; a++) {
                if (finals >= 70) {
                    d++;
                    finals -= 70;
                    weightcalculate += 70;
                }

            }

            if (d == 0) {
                document.getElementById('req35').value = null;
            } else {
                document.getElementById('req35').value = d;
            }
        }

        var avail25 = document.getElementById('avail25').value;

        if (avail25 == 0) {
            document.getElementById('req25').value = null;

        } else {
            //counts the required plates
            var e = 0;
            for (var a = 1; a <= avail25; a++) {
                if (finals >= 50) {
                    e++;
                    finals -= 50;
                    weightcalculate += 50;
                }

            }
            if (e == 0) {
                document.getElementById('req25').value = null;
            } else {
                document.getElementById('req25').value = e;

            }

        }

        var avail10 = document.getElementById('avail10').value;

        if (avail10 == 0) {
            document.getElementById('req10').value = null;

        } else {
            //counts the required plates
            var f = 0;
            for (var a = 1; a <= avail10; a++) {
                if (finals >= 20) {
                    f++;
                    finals -= 20;
                    weightcalculate += 20;
                }

            }
            if (f == 0)
            {
                document.getElementById('req10').value = null;
            } else {

                document.getElementById('req10').value = f;

            }

        }

        var avail5 = document.getElementById('avail5').value;

        if (avail5 == 0) {
            document.getElementById('req5').value = null;

        } else {
            //counts the required plates
            var g = 0;
            for (var a = 1; a <= avail5; a++) {
                if (finals >= 10) {
                    g++;
                    finals -= 10;
                    weightcalculate += 10;
                }

            }
            if (g == 0) {
                document.getElementById('req5').value = null;
            } else {
                document.getElementById('req5').value = g;
            }

        }

        var avail2 = document.getElementById('avail2').value;

        if (avail2 == 0) {
            document.getElementById('req2').value = null;

        } else {
            //counts the required plates
            var h = 0;
            for (var a = 1; a <= avail2; a++) {
                if (finals >= 5) {
                    h++;
                    finals -= 5;
                    weightcalculate += 5;
                }

            }

            if (h == 0) {
                document.getElementById('req2').value = null;
            }
            else {
                document.getElementById('req2').value = h;

            }

        }

        var bar2 = document.getElementById('Bar').value;
        document.getElementById('finalw').value = Math.floor(parseInt(weightcalculate) + parseInt(bar2));
        var targ = document.getElementById('Target').value;
        var finalssweight = document.getElementById('finalw').value;

        document.getElementById('diff').value = Math.floor(parseInt(targ) - parseInt(finalssweight));

    }
</script>