Several usages of JS to generate random numbers

Several usages of JS to generate random numbers

<script>  
function GetRandomNum(Min,Max)
{  
var Range = Max - Min;  
var Rand = Math.random();  
return(Min + Math.round(Rand * Range));  
}  
var num = GetRandomNum(1,10);  
alert(num);  
</script>

var chars = ['0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z'];

function generateMixed(n) {
   var res = "";
   for(var i = 0; i < n ; i ++) {
     var id = Math.ceil(Math.random()*35);
     res += chars[id];
   }
   return res;
}

1.Math.random();The result is a random number between 0 and 1 (including 0, excluding 1)

2. Math.floor (num);The parameter num is a numeric value and the result of the function is the integer part of num.

3. Math.round (num);The parameter num is a numeric value and the result of the function is an integer rounded to 5 by num4.

Math: A mathematical object that provides a mathematical calculation of data.
Math.random();Returns a random number between 0 and 1, including 0 and excluding 1.

Math.ceil (n);Returns the smallest integer greater than or equal to n.
Use Math.ceil (Math.random()*10);When 0 is used, the probability of obtaining a random integer from 1 to 10 is very small.

Math.round (n);Returns the value of an integer rounded to 5 by n4.
Use Math.round (Math.random());Random integers from 0 to 1 can be equally obtained.
Use Math.round (Math.random()*10);A random integer of 0 to 10 can be obtained equally, with the probability of obtaining the minimum value 0 and the maximum value 10 being less than half.

Math.floor (n);Returns the largest integer less than or equal to n.
Use Math.floor (Math.random()*10);A random integer of 0 to 9 can be obtained equally.