Java Metamorphic Step Implementation Ideas and Codes
- 2021-06-28 12:25:20
- OfStack
Metamorphic Step Jump
1. Title Description
A frog can jump up one step or two steps at a time... It can also jump up n.Find out how many jumps the frog can make up an n step.
2. Topic Analysis
f(1) = 1 f (2) has two ways of jumping, first or second order, which returns to the question f (1).f(2) = f(2-1) + f(2-2)
f (3) has three jumping modes: first, second, and third order, so it is left after the first jump out of the first order: f (3-1);Jump out of the second order for the first time, leaving f (3-2);The first third order leaves f (3-3). So the conclusion is:
f(3) = f(3-1)+f(3-2)+f(3-3)
When f (n), there will be n jump mode, first, second and n order, and conclude:
f(n) = f(n-1)+f(n-2)+...+f(n-(n-1)) + f(n-n) = > f(0) + f(1) + f(2) + f(3) + ... + f(n-1) == f(n) = 2*f(n-1)
3. Solution code
public class Solution {
public int JumpFloor(int target) {
if(target==0){
return 0;
}
if(target==1){
return 1;
}
return 2 * JumpFloor(target-1);
}
}
summary