echo 多行文字到文本

这篇文章为了记录自己写Dockerfile时踩的坑，分三部分描述echo内容到文件的用法

1. shell 脚本 echo 单行文字到文本
2. shell 脚本 echo 多行文字到文本
3. Dockerfile 中 echo 多行文字到文本

简要说明

在C++中，比较两个string字符串相等，通常使用的是 ==，这也是因为string类中，对 == 运算符对应的方法做了重载。

同样的 == ，在Java中，用法可是完全不一样的；今天就说说Java字符串String判断是否相等的equals和 == 的区别。

942. DI String Match

Easy

Given a string S that only contains “I” (increase) or “D” (decrease), let N = S.length.

Return any permutation A of [0, 1, ..., N] such that for all i = 0, ..., N-1:

• If S[i] == "I", then A[i] < A[i+1]

• If S[i] == "D", then A[i] > A[i+1]

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627. Swap Salary

Easy

SQL Schema

Given a table salary, such as the one below, that has m=male and f=female values. Swap all f and m values (i.e., change all f values to m and vice versa) with a single update statement and no intermediate temp table.

Note that you must write a single update statement, DO NOT write any select statement for this problem.

728. Self Dividing Numbers

Easy

A self-dividing number is a number that is divisible by every digit it contains.

For example, 128 is a self-dividing number because 128 % 1 == 0, 128 % 2 == 0, and 128 % 8 == 0.