Question

我有一个递归算法的伪代码，可以找到数组中第k个最大的数字。伪代码使用从索引1开始的数组，但是当我实际编写代码时，我需要数组从索引0开始。我无法弄清楚如何调整算法来做到这一点。

    var customer = function () {
     var name = "Contoso";
     return {
          getName: function () {
                return name;
          },
          setName: function (newName) {
                name = newName;
          }
     };
}();
alert (customer.name);

我意识到不需要对算法进行任何更改，只需要进行初始调用。但是，当我这样做时，它并没有给我正确的价值。如果这是问题，这是我的实际代码：

Select-kth-Algorithm4(A: array [1…n] of n distinct integers; left, right, k: integers between 1 and n)
pivotIndex = a randomly generated integer such that left≤pivotIndex≤right
pivotNewIndex = partition(A, left, right, pivotIndex)
if pivotNewIndex−left≥k then
    return Select-kth-Algorithm4(A, left, pivotNewIndex−1, k)
else if pivotNewIndex−left=k−1 then
    return A[pivotNewIndex]
else
    return Select-kth-Algorithm4(A, pivotNewIndex+1, right, k−pivotNewIndex+left−1)
//(Initial call to this algorithm should be Select-kth-Algorithm4(A,1, n, 5) for any particular value of n.}

partition(A, left, right, pivotIndex)
pivotValue = A[pivotIndex]
swap A[pivotIndex] and A[right]
storeIndex = left
for i = left to (right−1)
if A[i] > pivotValue then
    swap A[storeIndex] and A[i]
    storeIndex = storeIndex + 1
swap A[right] and A[storeIndex] 
return storeIndex

使用从1开始的Array索引转换算法

0 个答案: