https://leetcode.com/problems/climbing-stairs/description/
Climbing Stairs
state: f[i]表示前i个位置,跳到第i个位置的方案 总数
function: f[i] = f[i-1] + f[i-2] intialize: f[0] = 1
answer: f[n]
class Solution {
public int climbStairs(int n) {
if (n <= 0) {
return 0;
} else if (n <= 2) {
return n;
}
int[] ways = new int[n];
ways[0] = 1;
ways[1] = 2;
for (int i = 2; i < n; i++) {
ways[i] = ways[i - 1] + ways[i - 2];
}
return ways[n - 1];
}
}
