Find Factorial Value from Input Number

Source:
var n; function calculatefactorial(n){ if(n==0){ return 1; }else{ return n*calculatefactorial(n-1); } } var number=prompt("Enter a Numver: ","1"); alert(calculatefactorial(number)); document.writeln("Factorial of Your input ("+number+") "+"is: "+calculatefactorial(number));
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