【LeetCode】70. Climbing Stairs

LeetCode-70

Links:https://leetcode.com/problems/climbing-stairs/

You are climbing a stair case. It takes n steps to reach to the top.

Each time you can either climb 1 or 2 steps. In how many distinct ways can you climb to the top?

SoEazy … Fibonacci

class Solution {
public:
    int climbStairs(int n) {
        int a = 1,b = 2;
        if(n==1)return a;
        else if(n==2)return b;
        else {
            for(int i=2;i<n;i++)
            {
                b = a+b;
                a = b-a;
            }
            return b;
        }
    }
};

class Solution {

public:

int climbStairs(int n) {

int a = 1,b = 2;

if(n==1)return a;

else if(n==2)return b;

else {

for(int i=2;i<n;i++)

{

b = a+b;

a = b-a;

}

return b;

}

};

【LeetCode】70. Climbing Stairs

Tagged on: LeetCode