Array of arrays

Recursion + Loop

let array = [[["c",["a"]],[["bc"],["cdef"]]]]
let result = []

function collection(arr){
    for(let i = 0; i<arr.length; i++){
        if(Array.isArray(arr[i])){
            collection(arr[i]) //再次执行collection函式 所以会一直判断是否为阵列
        }
        else{
            result.push(arr[i])
        }
    }
    return result
}
console.log(collection(array))