---
id: afd15382cdfb22c9efe8b7de
title: DNA Pairing
isRequired: true
challengeType: 5
videoUrl: ''
localeTitle: DNA配对
---
## Description
DNA链缺少配对元素。获取每个字符，获取其对，并将结果作为二维数组返回。 碱基对是一对AT和CG。将缺少的元素与提供的字符匹配。将提供的字符作为每个数组中的第一个元素返回。例如，对于输入GCG，返回[[“G”，“C”]，[“C”，“G”]，[“G”，“C”]]字符及其对在一个中配对数组，并将所有数组分组到一个封装数组中。如果卡住，请记得使用Read-Search-Ask 。尝试配对程序。编写自己的代码。
## Instructions
## Tests
```yml
tests:
- text: 'pairElement("ATCGA")应返回[["A","T"],["T","A"],["C","G"],["G","C"],["A","T"]] 。'
testString: assert.deepEqual(pairElement("ATCGA"),[["A","T"],["T","A"],["C","G"],["G","C"],["A","T"]]);
- text: 'pairElement("TTGAG")应返回[["T","A"],["T","A"],["G","C"],["A","T"],["G","C"]] 。'
testString: assert.deepEqual(pairElement("TTGAG"),[["T","A"],["T","A"],["G","C"],["A","T"],["G","C"]]);
- text: 'pairElement("CTCTA")应返回[["C","G"],["T","A"],["C","G"],["T","A"],["A","T"]] 。'
testString: assert.deepEqual(pairElement("CTCTA"),[["C","G"],["T","A"],["C","G"],["T","A"],["A","T"]]);
```
## Challenge Seed
```js
function pairElement(str) {
return str;
}
pairElement("GCG");
```
## Solution
```js
// solution required
```