题目地址

https://leetcode.cn/problems/build-the-equation/description/

题目描述

Example 2:

输入: 
Terms 表:
+-------+--------+
| power | factor |
+-------+--------+
| 4     | -4     |
| 2     | 1      |
| 1     | -1     |
+-------+--------+
输出: 
+-----------------+
| equation        |
+-----------------+
| -4X^4+1X^2-1X=0 |
+-----------------+

代码

with t0 as(
    select power, (case when factor>0 then concat("+",factor) else factor end) as factor
    from  Terms
)
,
t1 as(
    select *,
    (case when power=0 then factor when power=1 then concat(factor,"X") 
    else concat(factor, "X^", power )  end ) as term
    from t0
    order by power desc
)

select concat( group_concat(term order by power desc separator ""),  "=0") as equation
from t1