2.3-2重写MERGE

#include<cstdio>
using namespace std;
int MERGE(int *A, int p, int q, int r){
int n1 = q - p + 1;
int n2 = r - q;
int L[1000],R[1000];
//初始化数组L[]R[]为无穷大；
for(int i = 0; i <= n1+1; i++)
L[i] = 1 << 30;
for(int i = 0; i <= n2+1; i++)
R[i] = 1 << 30;

//分别向数组L[]R[]赋值;
for(int i = 1; i <= n1;i++)
L[i] = A[p + i - 1];
for(int j = 1; j <= n2;j++)
R[j] = A[q+j];
//重新定义i,j（之前在以上四个for循环中定义的i,j寿命只限于其所在的for循环中）；
int i = 1;
int j = 1;
//进行归并；
for(int k = p; k <= r; k++){
if(L[i] <= R[j]){
A[k] = L[i];
i++;
continue;
}
else
{
A[k] = R[j];
j++;
continue;
}
if(i >= n1 && j < n2){
A[k] = R[j];
j++;
continue;
}
if(i < n1 && j >= n2){
A[k] = L[i];
i++;
continue;
}
}
}
int MERGE_SORT(int *A,int p,int r)
{
if(p < r)
{
int q = ((p+r)/2);
//进行递归；
MERGE_SORT(A,p,q);
MERGE_SORT(A,q+1,r);
MERGE(A,p,q,r);
}
}
int main()
{
int A[1000];
int p,r,n;
scanf("%d",&n);
p = 1;
r = n;
printf("输入原数组：\n");
for(int i = 1;i <= n;i++)
scanf("%d",&A[i]);
MERGE_SORT(A,p,r);
printf("归并后的结果为:\n");
for(int j = 1;j <= n;j++)
printf("%d ",A[j]);
return 0;
}