数组全排序

permutation

/*******************
 * javascript
 *第一种方式实现全排序
 *******************
 */
var result = [];

function permutation1(arr) {
  perm1(arr, 0);
  document.write(result.join('<br />'));
}

function perm1(arr, index) {
  var n = arr.length,
      j;
      
  if (index === n - 1) {
    result.push(arr.slice());
    return false; 
  } else {
    
    for (j = index; j < n; ++j) {
      swap(arr, j, index);
      arguments.callee(arr, j + 1);
      swap(arr, j, index);
    }
    
  }
}

function swap(arr, index1, index2) {
  var temp = arr[index1];
  arr[index1] = arr[index2];
  arr[index2] = temp;
}
/*************************
 * javascript
 * 第二种方式实现全排序
 * **********************
 */
var result = [],
    temp = [];
function permutation2(arr) {
  var n = arr.length,
      i;
  
  for (i = 0; i < n; ++i) {
    temp[i] = 0;
  }
  
  perm2(arr, n - 1);
  
  document.write(result.join('<br />'));
}

function perm2(arr, index) {
  var n = arr.length;
      i;
  if (index === 0) {
    result.push(temp.slice());
    return false;
  } else {
    
    for (i = 0; i < n; ++i) {
      if (temp[i] === 0) {
        temp[i] = arr[index];
        auguments.callee(arr, index - 1);
        temp[i] = 0;
      }
    }
  
  }
}