Introduction to Algorithms--seventh chapter, Quick Sort

1. Quick Sort Description:

It is divided into three parts: decomposition, settlement and merger based on the divide-and-conquer model;

1) Decomposition:

A[p the array: R] divided into two sub-arrays a[p: Q-1] and A[Q+1..R], yes a[p. Q-1] Each element is less than or equal to a (q)

2) Resolve:

Quick ordering by recursive invocation, a[p of the subarray. Q-1] and A[Q+1..R] Sort

3) Merger:

Merge two ordered arrays, a[p. R

1#include <stdio.h>2#include <stdlib.h>3 4 #defineMaxSize 85 6 intPartition (intA[],intPintR) {7     intx = A[r];//the last element in a[] as the principal, the Datum8     inti = P-1;9     intJ;Ten     inttmp; One      A     //through for () {...} Divide the array, because the last element is the principal, so J < (R-1) -      for(j = P; J < R; J + +){ -         if(A[j] <= x) {//The element is smaller than the primary, placed in front, and swapped two elements for position, I <= J thei = i +1; -              -TMP =A[i]; -A[i] =A[j]; +A[J] =tmp; -     //printf ("\nswaped:a[%d]:%d, a[%d]:%d\n", I, J, A[i], a[j]); +         } A     } at     //Place The main element between less than and greater than two parts -TMP = A[i +1]; -A[i +1] =A[r]; -A[R] =tmp; -      -     return(i +1); in } -  to voidQuickSort (intA[],intPintR) { +     if(P <R) { -         intQ; the          *Q =Partition (A, p, R); $QuickSort (A, p, Q-1);Panax NotoginsengQuickSort (A, q +1, R); -     } the } +  A intMain () { the     intA[maxsize] = {2,1,1,1,3,5,6,4}; +     inti; -      $printf"a[]...\n"); $      for(i =0; i < MaxSize; i++){ -printf"%d", A[i]); -     } the      -QuickSort (A,0, (MaxSize-1));Wuyi      theprintf"\nsorted a[]...\n"); -      for(i =0; i < MaxSize; i++){ Wuprintf"%d", A[i]); -     } Aboutprintf"\ n"); $          -System"Pause"); -     return 0; -}

Introduction to Algorithms--seventh chapter, Quick Sort