How many nodes does a leftist tree with r nodes must have?

(a) 2^r

(b) 2^r-1

(c) 2r

(d) 2r-1

My doubt is from Heap in section Heap of Data Structures & Algorithms I

I got this question in an interview.

How many nodes does a leftist tree with r nodes must have?

(a) 2^r

(b) 2^r-1

(c) 2r

(d) 2r-1

My doubt is from Heap in section Heap of Data Structures & Algorithms I

I got this question in an interview.