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@Chilling 2016-08-19T18:02:26.000000Z 字数 3364 阅读 1138

swustoj-2245: Skewed Sorting


Description

Farmer John has (1 <= N <= 10) cows, each conveniently labeled with paint on her flank with a number in the range 1... They are standing in a line in some random order. The first cow in line is cow_1; the second cow in line is cow_2; and so on (1 <= cow_i <=). Of course, cow_1 is unlikely to carry the painted label 1.

He performs the following algorithm to put them in order.

  1. If there is more than one cow, then partition the cows into two equal-sized sub-groups. Sort the first sub-group using this algorithm and then sort the second sub-group, also using this algorithm.

  2. Consider the current set of cows to be sorted as an equal-length pair of (potentially huge) base 2^N numbers. If the second number is smaller than the first one, then swap all the elements of the second one with those elements of the first one.

The cows would like to know how much distance they cover while moving around during this 'sorting' procedure.

Given the initial configuration of the cows, process the list according to the algorithm above and then print out:

By way of example, consider this line of =8 cows:

    8 5 2 3 4 7 1 6

First, Farmer John will sort each half of the line separately:

    8 5 2 3 | 4 7 1 6

Since each half still has more than one cow, Farmer John will sort those halves separately; starting with the 'first' half:

    8 5 | 2 3

Partitioning again, FJ makes

    8 | 5      and        2 | 3

each of which can be sorted by second rule, ultimately yielding:

    5 | 8      and        2 | 3 (<--unchanged)

The distance traveled by each cow during the first subgroup's sort is 1, so total_distance_moved becomes 2. The second half is already sorted, so the total_distance_moved stays at 2. The new configuration of this sub-group is:

    5 8 | 2 3

For step 2 of the algorithm on the subgroup above, we compare the two sides lexicographically (5 8 vs. 2 3). Since the 2 comes before 5, we swap the two elements of the first half with the corresponding elements of the second half, yielding:

    2 3 5 8

Each of the four cows moved two spaces in this swap, contributing a total of 8 moves, so total_distance_moved becomes 10.

Consider the other half of the cows; we divide the list of four into two sub-groups:

    4 7 | 1 6

Each pair (4, 7) and (1, 6) is already sorted.

Comparing (4 7) to (1 6), since 1 comes before 4, we must swap the two sub-groups:

    1 6 4 7

which contributes a total of 8 more moves, bringing total_distanced_move to 18.

After the operations above, the list looks like this (and it's time for step 2 to be performed on the two groups of 4):

    2 3 5 8 | 1 6 4 7

Since 1 comes before 2, we must swap the halves, this yielding this configuration:

    1 6 4 7 2 3 5 8

Since each of 8 cows moved four units, this contributes a total of 32 more moves, making total_distance_moved become 50

Therefore, the answer is 50 and 1 6 4 7 2 3 5 8.

Input

Output

Sample Input

3
8
5
2
3
4
7
1
6

Sample Output

50
1
6
4
7
2
3
5
8

  1. #include<stdio.h>
  2. #include<math.h>
  3. int count,a[11111],b[11111];
  4. void sort2(int m[],int temp[],int start,int mid,int end)
  5. {
  6. int i=start,j=mid+1,cnt=0;
  7. if(m[start]>m[mid+1])
  8. {
  9. while(j<=end)
  10. temp[cnt++]=m[j++];
  11. while(i<=mid)
  12. temp[cnt++]=m[i++];
  13. count+=(mid-start+1)*(mid-start+1)*2;
  14. }
  15. else
  16. {
  17. while(i<=mid)
  18. temp[cnt++]=m[i++];
  19. while(j<=end)
  20. temp[cnt++]=m[j++];
  21. }
  22. for(i=0;i<cnt;i++)
  23. m[i+start]=temp[i];
  24. }
  25. void sort1(int m[],int temp[],int start,int end)
  26. {
  27. if(start==end)return;
  28. int mid=(start+end)/2;
  29. sort1(m,temp,start,mid);
  30. sort1(m,temp,mid+1,end);
  31. sort2(m,temp,start,mid,end);
  32. }
  33. int main()
  34. {
  35. int n,i;
  36. while(scanf("%d",&n)!=EOF)
  37. {
  38. n=pow(2,n);
  39. count=0;
  40. for(i=0;i<n;i++)
  41. scanf("%d",&a[i]);
  42. sort1(a,b,0,n-1);
  43. printf("%d\n",count);
  44. for(i=0;i<n;i++)
  45. printf("%d\n",b[i]);
  46. }
  47. return 0;
  48. }
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