70. Climbing Stairs

    /*
     * 70. Climbing Stairs 
     * 2016-5-10 by Mingyang
     * Easy dp
     */
    public int climbStairs(int n) {
        if(n == 0 || n == 1 || n == 2){return n;}
        int[] dp = new int[n];
        dp[0] = 1;
        dp[1] = 2;
        for(int i = 2; i < n; i++){
            dp[i] = dp[i-1] + dp[i-2];
        }
        return dp[n-1];
    }