Bubble Sort

Bubble Sort

Write a program of the Bubble Sort algorithm which sorts a sequence A in ascending order. The algorithm should be based on the following pseudocode:

BubbleSort(A)
1 for i = 0 to A.length-1
2     for j = A.length-1 downto i+1
3         if A[j] < A[j-1]
4             swap A[j] and A[j-1]

Note that, indices for array elements are based on 0-origin.

Your program should also print the number of swap operations defined in line 4 of the pseudocode.

Input

The first line of the input includes an integer N, the number of elements in the sequence.

In the second line, N elements of the sequence are given separated by spaces characters.

Output

The output consists of 2 lines.

In the first line, please print the sorted sequence. Two contiguous elements of the sequence should be separated by a space character.

In the second line, please print the number of swap operations.

Constraints

1 ≤ N ≤ 100

Sample Input 1

5
5 3 2 4 1

Sample Output 1

1 2 3 4 5
8

Sample Input 2

6
5 2 4 6 1 3

Sample Output 2

1 2 3 4 5 6
9

#include <iostream>
#include <algorithm>
using namespace std;
const int MAX = 110;
int a[MAX];
int sum;
void BubbleSort(int a[], int n)
{
	for(int i = 0; i < n - 1; ++ i)
	{
		for(int j = n - 1; j >= i + 1; -- j)
		{
			if(a[j] < a[j - 1])
			{
				swap(a[j], a[j - 1]);
				sum ++;
			}
		}
	}
} 
//void BubbleSort(int a[], int n)
//{
//	int flag = 1;	// 存在顺序相反的相邻元素 
//	for(int i = 0; flag; ++ i)
//	{
//		flag = 0;
//		for(int j = n - 1; j > i; -- j)
//		{
//			if(a[j] < a[j - 1])
//			{
//				swap(a[j], a[j - 1]);
//				flag = 1;
//				sum ++;
//			}
//		}
//	}
//} 
int main()
{
	int n;
	cin >> n;
	for(int i = 0; i < n; ++ i)
	{
		cin >> a[i];
	}
	
	BubbleSort(a, n);
	
	for(int i = 0; i < n; ++ i)
	{
		if(i == n - 1)
			cout << a[i];
		else
			cout << a[i] << " ";
	}
	cout << endl;
	cout << sum << endl;
	
	return 0;
}

  

原文地址:https://www.cnblogs.com/mjn1/p/10702129.html