I don't understand exactly how the result of this code is here, why the output is like this?-CodePudding

I failed to find out reason of the output: 337

function mlt(a, b){
    if(!(a&&b)) {
        return 0;
    }else if(b==1){
        return a;
    } else {
        return (a   mlt(a, b-1));
    }
}
document.write(mlt(3, 11));
document.write(mlt(7, 1));

CodePudding user response：

lets do this in simple way:

mlt(3,11) :
false false true => return 3   mlt(3, 10)
false false true => return 3   3   mlt(3 , 9)
false false true => return 3   3   3  mlt(3 , 8)
false false true => return 3   3   3   3   mlt(3 , 7)
false false true => return 3   3   3   3   3   mlt(3 , 6)
false false true => return 3   3   3   3   3   3   mlt(3 , 5)
false false true => return 3   3   3   3   3   3   3   mlt(3 , 4)
false false true => return 3   3   3   3   3   3   3   3   mlt(3 , 3)
false false true => return 3   3   3   3   3   3   3   3   3   mlt(3 , 2)
false false true => return 3   3   3   3   3   3   3   3   3   3   mlt(3 , 1)

summation of the 3 equal to 30 mlt(3,1)

mlt(3,1) : false true false So equal to a = 3

First output is 33

mlt(7,1) : false true false So equal to a = 7

Final output is 337

33 for mlt(3,11)
7 for mlt(7,1)

Happy codding :)

CodePudding user response：

You're getting 337 simply because the results of your two function calls are 33 and 7 respectively. Since you're writing this with document.write its simply appending the 7 to the end of the 33 resulting in 337

document.write(mlt(3, 11)); returns 33 document.write(mlt(7, 1)); returns 7