请把两个数组 ['A1', 'A2', 'B1', 'B2', 'C1', 'C2', 'D1', 'D2'] 和 ['A', 'B', 'C', 'D']，合并为 ['A1', 'A2', 'A', 'B1', 'B2', 'B', 'C1', 'C2', 'C', 'D1', 'D2', 'D']。
答案
function concatArr (arr1, arr2) {
const arr = [...arr1];
let currIndex = 0;
for (let i = 0; i < arr2.length; i++) {
const RE = new RegExp(arr2[i])
while(currIndex < arr.length) {
++currIndex
if (!RE.test(arr[currIndex])) {
arr.splice(currIndex, 0, a2[i])
break;
}
}
}
return arr
}
var a1 = ['A1', 'A2', 'B1', 'B2', 'C1', 'C2', 'D1', 'D2']
var a2 = ['A', 'B', 'C', 'D']
const arr = concatArr(a1, a2)
console.log(a1) // ['A1', 'A2', 'B1', 'B2', 'C1', 'C2', 'D1', 'D2']
console.log(a2) // ['A', 'B', 'C', 'D']
console.log(arr) // ['A1', 'A2', 'A', B1', 'B2', 'B', C1', 'C2', 'C', D1', 'D2', 'D']
标签：arr,30,合并,currIndex,A1,A2,数组,C2,C1 From： https://www.cnblogs.com/zhanghaian/p/16668420.html