JavaScript implements exhaustive permutation (permutation) algorithm puzzle solution_javascript skills

Puzzle

Exhaustively list the arrangements of each element in an array

Strategy

Reduce and cure, recursion

JavaScript Solution

Copy code The code is as follows:

/**
 * Created by cshao on 12/23/14.
 */

function getPermutation(arr) {
if (arr.length == 1) {
Return [arr];
}

var permutation = [];
for (var i=0; i var firstEle = arr[i];
var arrClone = arr.slice(0);
arrClone.splice(i, 1);
var childPermutation = getPermutation(arrClone);
for (var j=0; j childPermutation[j].unshift(firstEle);
}
Permutation = permutation.concat(childPermutation);
}
Return permutation;
}

var permutation = getPermutation(['a','b','c']);
console.dir(permutation);

Results

Copy code The code is as follows:

[ [ 'a', 'b', 'c' ],
[ 'a', 'c', 'b' ],
[ 'b', 'a', 'c' ],
[ 'b', 'c', 'a' ],
[ 'c', 'a', 'b' ],
[ 'c', 'b', 'a' ] ]