why it reverse the opration after it do?-CodePudding

I try to add a numbers from 1 to 10 by JavaScript using the concept of recursion and it didn't work as intended. it revers the operation and it come up with the first result and when i use variable to store the result i get it come up with undefined. here is the code

var total = 0, count = 1;
function sum(total, count){
    if(count <= 3){
        total  =count;
        count  ;
        sum(total, count);
    }else{
        return total;
    };
}
var result = sum(total, count);
console.log(result);

CodePudding user response：

You are not returning from your first if condition. Default return value for any function is undefined.

var total = 0, count = 1;
function sum(total, count){
    if(count <= 3){
        total  =count;
        count  ;
        return sum(total, count);
    }else{
        return total;
    };
}
var result = sum(total, count);
console.log(result);