Direct Insert sort straight insertion sort

1. The idea of direct insertion sequencing:

Insert a record into an ordered table that is already ordered, resulting in a new, sequential table with a 1 increase in the number of records.

1 voidInsertsort (SqList *L)2 {3     intI, J;4      for(i=2; i<=l->length; i++)5     {6         if(L->r[i] < l->r[i-1])7         {8l->r[0] = l->R[i];9              for(j=i-1; L-&GT;R[J] > l->r[0]; j--)Ten             { Onel->r[j+1] = l->R[j]; A             } -l->r[j+1] = l->r[0]; -         } the     } -}

2. Direct insertion sorting complexity analysis

space complexity: It only requires a record of the secondary space.

Complexity of Time:

Best case: The table itself is ordered, comparing only n-1 times, but without recording the movement, the time complexity is O (n).

Worst case scenario: The table itself is in reverse order, at which point you need to compare ∑i=2n (i) = 2+3+...+n = (n+2) (n-1)/2 times.

The number of records moved also reached the maximum ∑ni=2 (i+1) = (n+4) (n-1)/2 times.

So the average comparison and the number of moves is about N2/4 times, the time complexity is O (N2).

But the same O (N2) time complexity, the direct insert sorting method is better than bubbling and simple selection of sorting performance.

Direct Insert sort straight insertion sort