function pow(x, n) { if (n == 1) { return x; } else { return x * pow(x, n - 1); } } alert( pow(2, 3) );

Question

How to work this function

Answer 1

pow(2,3)

2*pow(2,2)

2*2*pow(2,1)

2*2*2

8

Answer 2

This is called Recursion means function calling function itself until the condition is not satisfying.

So here

pow(x, n) = pow(2, 3)
n = 3, x = 2

for n = 3, n == 1 //false so else will execute
= x * pow(x, n - 1)
= 2 * pow(2, 2) //now here n = 2

so for n = 2, n == 1 is false so else will execute
= 2 * (2 * pow(2, 1))

now here n = 1, so n == 1 will be true and method will return x means 2

so finally
= 2 * 2 * 2 = 8