Algorytm translacji drzewiastej JavaScript

Question

Potrzebuję pomocy w przechodzeniu przez strukturę drzewa na pierwszy rzut oka. Nie mogę wymyślić algorytmu, aby zrobić to poprawnie.

Moje wejście jest taka:

[ 
    ["A", "B", "C"], 
    ["1", "2"], 
    ["a", "b", "c", "d"] 
] 

Wyjście powinno przybrać formę:

[ 
    "A/1/a", "A/1/b", "A/1/c", "A/1/d", 
    "A/2/a", "A/2/b", "A/2/c", "A/2/d", 
    "B/1/a", "B/1/b", "B/1/c", "B/1/d", 
    "B/2/a", "B/2/b", "B/2/c", "B/2/d", 
    "C/1/a", "C/1/b", "C/1/c", "C/1/d", 
    "C/2/a", "C/2/b", "C/2/c", "C/2/d" 
] 

Answer 1

To powinno załatwić sprawę:

function traverse(arr) { 
 
    var first = arr[0]; 
 
    var ret = []; 
 
    if (arr.length == 1) { 
 
    for (var i = 0; i < first.length; i++) { 
 
     ret.push(first[i]); 
 
    } 
 
    } else { 
 
    for (var i = 0; i < first.length; i++) { 
 
     var inn = traverse(arr.slice(1)); 
 
     for (var j = 0; j < inn.length; j++) { 
 
     ret.push(first[i] + '/' + inn[j]); 
 
     } 
 
    } 
 
    } 
 
    return ret; 
 
} 
 

 
var inp = [ 
 
    ["A", "B", "C"], 
 
    ["1", "2"], 
 
    ["a", "b", "c", "d"] 
 
]; 
 

 
var out = traverse(inp); 
 

 
console.log(out);

Answer 2

Co szukasz jest iloczyn kartezjański listy list, został asked przed. Pożyczanie od przyjętego odpowiedź na to pytanie, można to zrobić w JavaScript 1.7:

function product() { 
    return Array.prototype.reduce.call(arguments, function(as, bs) { 
     return [a.concat(b) for each (a in as) for each (b in bs)]; 
    }, [[]]); 
}; 

function convert(lst) { 
    var solution = []; 
    for (var i = 0; i < lst.length; i++) { 
    solution.push(lst[i][0] + "/" + lst[i][1] + "/" + lst[i][2]); 
    } 
    return solution; 
}; 

convert(product(["A", "B", "C"], ["1", "2"], ["a", "b", "c", "d"])); 

> ["A/1/a", "A/1/b", "A/1/c", "A/1/d", 
    "A/2/a", "A/2/b", "A/2/c", "A/2/d", 
    "B/1/a", "B/1/b", "B/1/c", "B/1/d", 
    "B/2/a", "B/2/b", "B/2/c", "B/2/d", 
    "C/1/a", "C/1/b", "C/1/c", "C/1/d", 
    "C/2/a", "C/2/b", "C/2/c", "C/2/d"]