第一题

class Solution {
    public String convertDateToBinary(String date) {
        String[] s = date.split("-");
        int year = Integer.parseInt(s[0]);
        int mouth = Integer.parseInt(s[1]);
        int day = Integer.parseInt(s[2]);

        String binaryYear = Integer.toBinaryString(year);
        String binaryMouth = Integer.toBinaryString(mouth);
        String binaryDay = Integer.toBinaryString(day);

        return binaryYear + "-" + binaryMouth + "-" + binaryDay;

    }
}

第二题

class Solution {
    public int maxPossibleScore(int[] start, int d) {
        Arrays.sort(start);
        int n = start.length;
        if(n == 2) return start[1] + d - start[0];
        int l = 0, r = Integer.MAX_VALUE;

        while(l < r)
        {
            int mid = l + r + 1 >> 1;
            if(check(start, mid, d)) l = mid;
            else r = mid - 1;
        }

        return l;
    }

    public boolean check(int[] start, int diff, int d)
    {
        int prev = start[0];
        for(int i = 1; i < start.length; i ++ )
        {
            int low = start[i];
            int high = start[i] + d;
            if(prev + diff > high) return false;
            prev = Math.max(prev + diff, start[i]);
        }

        return true;
    }
}

第三题

class Solution {
    public long findMaximumScore(List<Integer> nums) {
        long sum = 0;
        long mx = 0;

        for(int i = 0; i + 1 < nums.size(); i ++ )
        {
            mx = Math.max(mx, nums.get(i));
            sum += mx;
        }

        return sum;
    }
}