算法随想录算法训练营第二十八天|122.买卖股票的最佳时机II 55. 跳跃游戏 45.跳跃游戏II

122.买卖股票的最佳时机II 

class Solution {
    public int maxProfit(int[] prices) {
        int res = 0;
        for(int i = 1;i0){
                res= res+(prices[i]-prices[i-1]);
            }
        }
        return res;
    }
}

55. 跳跃游戏 

class Solution {
    public boolean canJump(int[] nums) {
        int maxLength = 0;
        for(int i = 0;i=nums.length-1)
            return true;
        else
            return false;
    }
}

45.跳跃游戏II

class Solution {
    public int jump(int[] nums) {
        if(nums.length<=1)
            return 0;
        int[] res = new int[nums.length];
        Arrays.fill(res,Integer.MAX_VALUE);
        res[0] = 0;
        for(int index = 0;index= nums.length-1)
                return res[index]+1;
            while(start<=index+nums[index]){
                res[start] = Math.min(res[start],res[index]+1);
                start++;
            }
        }
        return res[nums.length-1];
    }
}