public static int f(int n) {
if (n <= 1) return 1;
return f(n-1) + 2 * f(n-2);
}
// Call: System.out.println(f(5));What is printed?
- Acheck_circle
21
- B
31
- C
11
- D
32
Explanation
f(0)=1, f(1)=1. f(2)=f(1)+2<em>f(0)=1+2=3. f(3)=f(2)+2</em>f(1)=3+2=5. f(4)=f(3)+2<em>f(2)=5+6=11. f(5)=f(4)+2</em>f(3)=11+10=21.