function calcsize(){
	var numericExpression = /^[0-9]+$/;
	var back1=(document.form1.backsize.value)
	var bust1=(document.form1.bustsize.value)
	{
		if(document.form1.bustsize.value == '' && document.form1.backsize.value == ''){
			document.form1.combined.value = 'Enter Your Size'
		}else{
			if (document.form1.backsize.value == ''){
				document.form1.combined.value = 'Enter Back Size'
				document.form1.bustsize.value = bust1
			}else{
				var back = Math.round(back1)
				document.form1.backsize.value = back

				if(document.form1.bustsize.value == ''){
					document.form1.combined.value = 'Enter Bust Size'
					document.form1.backsize.value = back1
				}else{

					var bust = Math.round(bust1)
					document.form1.bustsize.value = bust

					if(document.form1.bustsize.value.match(numericExpression) && document.form1.backsize.value.match(numericExpression)){
						bust = eval(document.form1.bustsize.value)
						back = eval(document.form1.backsize.value)

						if( back % 2 ){
							adjustedBack = back + 5
						}else{
							adjustedBack = back + 4
						}

						measDiff = bust - back
						if( measDiff > 15 || measDiff < 5 || back < 23 || bust < 28 || back > 44 || bust > 59){
							document.form1.combined.value = "Unavailable"
							document.form1.bustsize.value = bust1
							document.form1.backsize.value = back1
						}else{
							cup = cupSizes[measDiff]
							document.form1.combined.value = adjustedBack + cup
							document.form1.bustsize.value = bust1
							document.form1.backsize.value = back1
						}
					}else{
						document.form1.combined.value = 'Remove Letters'
						document.form1.bustsize.value =''
						document.form1.backsize.value =''
					}
				}
			}
		}
	}
}