Sort algorithm from bubbling sort of thought of

1, the algorithm thought description narration:

1) Compare the adjacent two numbers, assuming that the previous one is larger than the one in the back, then they will be exchanged. Each cycle enables a number to reach an orderly state.

2. Complexity of Time:

Average O (n^2). Best: O (N), at the beginning of the sequence is a positive sequence of the time to obtain

3, implementation and optimization.

Here are three ways to implement

/* * bubblesort.cpp * * Created on:2014 May 17 * author:pc * * #include <iostream> #include <cstdio> #inclu De <ctime>using namespace Std;const int maxn = 10;int arr[maxn];/** * First switching algorithm: * With the help of intermediate variables */void swap1 (int arr[],int i , int j) {int temp = Arr[i];arr[i] = arr[j];arr[j] = temp;} /** * Another switching algorithm: * Without intermediate variables, using arithmetic operations */void swap2 (int arr[],int i, int j) {Arr[i] = Arr[i] + arr[j];arr[j] = arr[i]-Arr[j];ar R[i] = Arr[i]-arr[j];} /** * Third Exchange algorithm: * Use bitwise operation */void SWAP3 (int arr[], int i, int j) {Arr[i] = arr[i]^arr[j];arr[j] = Arr[i]^arr[j];arr[i] = Arr[i] ^ARR[J];} /** * The first way to bubble sort: * Standard way */void bubblesort1 (int arr[],int n) {int I;int j;for (i = 0; i < n; ++i) {//Loop n-1 times, each can be a number to an orderly state for (j = 0; j < n-i-1; ++j) {//each time the number before the first number to the ordered state is compared (the number after the ordered state is no longer required) if (Arr[j] > Arr[j+1]) {//assuming that the preceding number is greater than the subsequent number swap3 ( ARR,J,J+1);//The other way of exchanging}}}}/** * bubble sort: To optimize */void bubblesort2 (int arr[],int n) {int] by "Scanning again, if there is no exchange, that is to achieve an orderly State" feature K = N;bool flag = true;while (flag) {flag = false;for (int j = 0; j < k-1; ++J) {if (Arr[j] > Arr[j+1]) {swap3 (arr,j,j+1); flag = true;//is used to mark whether the interchange has occurred this time}}--k;}} /** * The third way to bubble sort: On another basis, for processing "If there are 100 data, if the last 90 are already ordered" */void bubblesort3 (int arr[],int n) {int K;int flag = N;while ( Flag > 0) {k = Flag;flag = 0;for (int j = 1; j < K; ++j) {if (arr[j-1] > Arr[j]) {swap3 (arr,j-1,j); flag = j;//change to mode 2 Into... Used to mark which position the interchange occurred}}}}void Createreversearr () {int i = 0;for (i = 0; i < MAXN; ++i) {arr[i] = maxn-i;}} void Printarr () {int i;for (i = 0; i < MAXN; ++i) {printf ("%d", Arr[i]);} printf ("\ n");} time_t printtime (String str) {time_t now = time (NULL), cout << str << ":" <<now <<endl;return now;} /** * Gets the system current time */time_t GetTime () {time_t now = times (NULL); int main () {Createreversearr ();p Rintarr (); time_t before = GetTime (); Bubblesort3 (ARR,MAXN); time_t after = GetTime (); Printarr ();cout<< "cost:" <<after-before << "s" &LT;&LT;ENDL;}

Sort algorithm from bubbling sort of thought of