归并排序

#include<stdio.h>
#define MAXSIZE 20
typedef int KeyType;
typedef struct{
    KeyType  key;
}RcdType;
typedef struct {
    RcdType r[MAXSIZE+1];
    int length;
}Sqlist;
void Merge(RcdType sr[],RcdType tr[],int s,int m,int t)
{
    int i, k,j;
    j=m+1;i=s;k=s;
    while(i<=m&&j<=t)
    if(sr[i].key<=sr[j].key)
        tr[k++]=sr[i++];
    else 
        tr[k++]=sr[j++];
    while(i<=m)
        tr[k++]=sr[i++];
    while(j<=t)
        tr[k++]=sr[j++]; 

}
void Msort(RcdType sr[],RcdType tr1[],int s,int t){
 int m;
 RcdType tr2[MAXSIZE+1];
    if(s==t)
        tr1[s]=sr[s];
    else{
        m=(s+t)/2;
        Msort(sr,tr2,s,m);
        Msort(sr,tr2,m+1,t);
        Merge(tr2,tr1,s,m,t);
    }
}
void  MergeSort(Sqlist &L)
{Msort(L.r,L.r,1,L.length);}
void main()
{Sqlist A;
 int i;
 printf("\n请输入待排序的个数");
 scanf("%d",&A.length);
 printf("\n请输入待排序的数字");
 for(i=1;i<=A.length;i++)
  scanf("%d",&A.r[i].key);
 MergeSort(A);
 printf("\n排好序的数字为");
 for(i=1;i<=A.length;i++)
  printf("%d ",A.r[i].key);
}