Recursive programming in JavaScript language_javascript skills

Question: What is the sum of adding up from 1 to 100?

Non-recursive loop writing:

Copy code The code is as follows:

1run: function() {
2 var sum = 0;
3 for(var i=1;i<=100;i ) {
4 sum = sum i;
5 }
6 console.log(sum);
7}

Recursive writing:

Copy code The code is as follows:

var testCase = {
sum: 0,
run: function(n) {
if(n>=100) {
return 100;
}
else {
sum = n testCase.run(n 1);
return sum;
}
}
};
console.log(testCase.run(1));

There are a lot of codes like the above found on the Internet. The following writing method is equivalent to it:

Copy code The code is as follows:

console.log((function(n){
var sum=0;
if(n<=1){
return 1;
}
else{
sum = arguments.callee(n-1) n;
return sum;
}
})(100));

This way of writing is easy to learn. The above is linear recursion, which is fine as an introduction to recursion. However, the performance efficiency of the algorithm is a bit poor and will not be considered.