插入排序 （Insert Sort）

Wiki ： http://en.wikipedia.org/wiki/Insertion_sort

看看下面的动态图片， 就明白插入排序是怎么回事了：

WiKi上给出的伪代码：

Pseudocode of the complete algorithm follows, where the arrays arezero-based:

 // The values in A[i] are checked in-order, starting at the second one for i ← 1 to i ← length(A)-1   {     // at the start of the iteration, A[0..i-1] are in sorted order     // this iteration will insert A[i] into that sorted order      // save A[i], the value that will be inserted into the array on this iteration     valueToInsert ← A[i]     // now mark position i as the hole; A[i]=A[holePos] is now empty     holePos ← i     // keep moving the hole down until the valueToInsert is larger than      // what's just below the hole or the hole has reached the beginning of the array     while holePos > 0 and valueToInsert < A[holePos - 1]       { //value to insert doesn't belong where the hole currently is, so shift          A[holePos] ← A[holePos - 1] //shift the larger value up         holePos ← holePos - 1       //move the hole position down       }     // hole is in the right position, so put valueToInsert into the hole     A[holePos] ← valueToInsert     // A[0..i] are now in sorted order   }