UVa 10810: Ultra-QuickSort (Solution)
Ultra-QuickSortIn this problem, you have to analyze a particular sorting algorithm. The algorithm processes a sequence of n distinct integers by swapping two adjacent sequence elements until the sequence is sorted in ascending order. For the input sequence
9 1 0 5 4
Ultra-QuickSort produces the output
0 1 4 5 9
Your task is to determine how many swap operations Ultra-QuickSort needs to perform in order to sort a given input sequence.
Input
The input contains several test cases. Every test case begins with a line that contains a single integer n < 50000, the length of the input sequence. Each of the the following n lines contains a single integer 0 ≤ a[i] < 10^10, the i-th input sequence element.
Input is terminated by a sequence of length n = 0. This sequence must not be processed.
The input must be read from standard input.
Output
For every input sequence, your program prints a single line containing the minimum number of swap operations necessary to sort the given input sequence.
The output must be written to standard output.
Sample Input
5
9
1
0
5
4
3
1
2
3
0
Your task is to determine how many swap operations Ultra-QuickSort needs to perform in order to sort a given input sequence.
Input
The input contains several test cases. Every test case begins with a line that contains a single integer n < 50000, the length of the input sequence. Each of the the following n lines contains a single integer 0 ≤ a[i] < 10^10, the i-th input sequence element.
Input is terminated by a sequence of length n = 0. This sequence must not be processed.
The input must be read from standard input.
Output
For every input sequence, your program prints a single line containing the minimum number of swap operations necessary to sort the given input sequence.
The output must be written to standard output.
Sample Input
5
9
1
0
5
4
3
1
2
3
0
Sample Output
6
0
SOLUTION: Python
6
0
SOLUTION: Python
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| ''' SOLUTION: Python Problem: http://onlinejudge-problems.blogspot.com/2015/09/uva-10810-ultra-quicksort-solution.html ''' | |
| from sys import stdin | |
| num,lenn = None,None | |
| def solve (num,low,hi): | |
| cont=0 | |
| if low+1<hi: | |
| mid=low+((hi-low)//2) | |
| cont= solve(num,low,mid) | |
| cont+=solve(num,mid,hi) | |
| cont+=(merge(num,low,hi,mid)) | |
| return cont | |
| def merge(num,low,hi,mid): | |
| cont=0 | |
| i,j=0,0 | |
| pparte,sparte=num[low:mid],num[mid:hi] | |
| for k in range(low,hi): | |
| if i==mid-low: | |
| num[k]=sparte[j] | |
| j+=1 | |
| elif j==hi-mid: | |
| num[k]=pparte[i] | |
| i+=1 | |
| else: | |
| if pparte[i]<=sparte[j]: | |
| num[k]=pparte[i] | |
| i+=1 | |
| else: | |
| num[k]=sparte[j] | |
| j+=1 | |
| cont+=((mid-low)-i) | |
| return cont | |
| def main(): | |
| global num,lenn | |
| inp = stdin | |
| lenn = int(stdin.readline()) | |
| while lenn>0: | |
| num = [ int(stdin.readline()) for i in range(lenn) ] | |
| print(solve(num,0,lenn)) | |
| lenn = int(stdin.readline()) | |
| main() |
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