数据结构-数组排序-二路归并-循环实现-C语言

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/*
 *
 * 归并排序-循环实现
 *
 * */

#include <stdio.h>
#include <stdlib.h>

void Merge(int Element[],int TmpA[],int L,int R,int RightEnd){
    int LeftEnd,NumElements,Tmp;
    LeftEnd=R-1;
    Tmp=L;
    NumElements=RightEnd-L+1;
    while (L<=LeftEnd&&R<=RightEnd){
        if(Element[L]<Element[R])TmpA[Tmp++]=Element[L++];
        else TmpA[Tmp++]=Element[R++];
    }
    while (L<=LeftEnd)TmpA[Tmp++]=Element[L++];
    while (R<=RightEnd)TmpA[Tmp++]=Element[R++];
    //for(int i=0;i<NumElements;i++,RightEnd--)Element[RightEnd]=TmpA[RightEnd];
}
void Merge_pass(int A[],int TmpA[],int N, int length){
    int i;
    //对"细度"为length进行成对排序
    for(i=0;i<=N-2*length;i+=2*length){
        Merge(A,TmpA,i,i+length,i+2*length-1);
    }
    if(i+length<N){
        Merge(A,TmpA,i,i+length,N-1);
    }
    else for(int j=i;j<N;j++)TmpA[j]=A[j];
}

void Merge_Sort(int A[],int N){
    int length;
    int * TmpA;
    length=1;
    TmpA=malloc(N* sizeof(int));
    if(TmpA!=NULL){
        //控制"细度"length
        while(length<N){
            Merge_pass(A,TmpA,N,length);
            length*=2;
            Merge_pass(TmpA,A,N,length);
            length*=2;
        }
        free(TmpA);
    }
    else printf("空间不足");
}

int main(){
    int c[10];
    for (int i = 0; i <10 ; i++) {
        c[i]=rand()%10;
    }
    printf("排序前:");
    for (int j = 0; j < 10; j++) {
        printf("%d  ",c[j]);
    }
    printf("\n排序后:");
    Merge_Sort(c,10);
    for (int j = 0; j < 10; j++) {
        printf("%d  ",c[j]);
    }

    return 0;
}