谁能帮我看看我这个归并排序错在什么地方了？

[quruichen]

#include <iostream>
using std::cout;
using std::endl;


const int ARRAY_SIZE = 100;

void merge(int A[], int const first, int const mid, int const last);
void merge_sort(int a[],int first,int last);

void merge(int A[], int const first, int const mid, int const last)
{
int left[ARRAY_SIZE/2+1],right[ARRAY_SIZE/2+1];
int left_size = mid - first;
int right_size = last - mid + 1;
int l,r,n;

for(l=0;l<left_size;l++)
left[l] = A[first+l];
for(r=0;r<right_size;r++)
right[r] = A[mid+r];

l=r=0;
n=first-1;

while ((l<left_size)&&(r<right_size))
{
n++;
if (left[l]<right[r])
A[n] = left[l++];
else
A[n] = right[r++];

}

if(l!=left_size-1)
{
while(l<=left_size-1) A[++n] = left[l++];
}
if (r!=right_size-1)
{
while(r<=right_size-1)A[++n] = right[r++];
}
}

void merge_sort(int a[],int first,int last)
{
int mid;
if (first<last)
{
mid=(first+last)/2+1;
merge_sort(a,first,mid-1);
merge_sort(a,mid,last);
merge(a,first,mid,last);
}
}

void main()
{
int a[ARRAY_SIZE]={846,4,78,46,12,547,54,47,33,51};
merge_sort(a,0,9);
for (int i=0;i<10;i++)
{
cout<<a[i]<<endl;
}
}

如题 就是弄不出来！结果总是不对！谢谢各位高手了！

[csdn5211]

帮你顶顶吧，建议自己跟进去调试，vc的话就加断点，gcc就用gdb。

[quruichen]

用了很多种办法了，可就是没法解决！ 各位大虾来帮帮我吧！！

[luxiaoxun]

#include <iostream> 
using std::cout; 
using std::endl; 


const int ARRAY_SIZE = 100; 

void merge(int A[], int const first, int const mid, int const last); 
void merge_sort(int a[],int first,int last); 

void merge(int A[], int const first, int const mid, int const last) 
{ 
int* a=new int[last-first+1];
int l=first,r=mid+1,n=0; 
int i;
while(l<=mid&&r<=last)
 if(A[l]<=A[r]) a[n++]=A[l++];
 else a[n++]=A[r++];
while(l <=mid) 
  a[n++] = A[l++]; 
while(r <=last) 
  a[n++] = A[r++]; 
for(i=0,n=first;n<=last;)
 A[n++]=a[i++];
 delete []a; 
} 

void merge_sort(int a[],int first,int last) 
{ 
int mid; 
if (first <last) 
{ 
mid=(first+last)/2; 
merge_sort(a,first,mid); 
merge_sort(a,mid+1,last); 
merge(a,first,mid,last); 
} 
} 

void main() 
{ 
int a[ARRAY_SIZE]={846,4,78,46,12,547,54,47,33,51}; 
merge_sort(a,0,9); 
for (int i=0;i <10;i++) 
{ 
cout <<a[i] <<endl; 
} 
} 

按归并排序的思路给你改了一下
Ps：以后发代码 按“#”选什么代码 这样别人好看

[星羽]

http://baike.baidu.com/view/19000.htm

[quruichen]

#include <iostream> 
using std::cout; 
using std::endl; 


const int ARRAY_SIZE = 100; 

void merge(int A[], int const first, int const mid, int const last); 
void merge_sort(int a[],int first,int last); 

void merge(int A[], int const first, int const mid, int const last) 
{ 
    int left[ARRAY_SIZE/2+1],right[ARRAY_SIZE/2+1]; 
    int left_size = mid - first; 
    int right_size = last - mid + 1; 
    int l,r,n; 
    
    for(l=0;l <left_size;l++) 
        left[l] = A[first+l]; 
    for(r=0;r <right_size;r++) 
        right[r] = A[mid+r]; 
    
    l=r=0; 
    n=first-1; 
    
    while ((l <left_size)&&(r <right_size)) 
    { 
        n++; 
        if (left[l] <right[r]) 
            A[n] = left[l++]; 
        else 
            A[n] = right[r++]; 
        
    } 
    
    //if(l!=left_size-1) 
    //{ 
        while(l <=left_size-1) A[++n] = left[l++]; 
    //} 
    //if (r!=right_size-1) 
    //{ 
        while(r <=right_size-1)A[++n] = right[r++]; 
    //} 
} 

void merge_sort(int a[],int first,int last) 
{ 
    int mid; 
    if (first <last) 
    { 
        mid=(first+last)/2+1; 
        merge_sort(a,first,mid-1); 
        merge_sort(a,mid,last); 
        merge(a,first,mid,last); 
    } 
}
void main() 
{ 
    int a[ARRAY_SIZE]={846,4,78,46,12,547,54,47,33,51}; 
    merge_sort(a,0,9); 
    for (int i=0;i <10;i++) 
    { 
        cout << a[i] <<endl; 
    } 
} 

[jia_xiaoxin]

其实你犯的错误很简单，就是注释掉的部分

#include <iostream> 
using std::cout; 
using std::endl; 


const int ARRAY_SIZE = 100; 

void merge(int A[], int const first, int const mid, int const last); 
void merge_sort(int a[],int first,int last); 

void merge(int A[], int const first, int const mid, int const last) 
{ 
	int left[ARRAY_SIZE/2+1],right[ARRAY_SIZE/2+1]; 
	int left_size = mid - first; 
	int right_size = last - mid + 1; 
	int l,r,n; 
	
	for(l=0;l <left_size;l++) 
		left[l] = A[first+l]; 
	for(r=0;r <right_size;r++) 
		right[r] = A[mid+r]; 
	
	l=r=0; 
	n=first-1; 
	
	while ((l <left_size)&&(r <right_size)) 
	{ 
		n++; 
		if (left[l] <right[r]) 
			A[n] = left[l++]; 
		else 
			A[n] = right[r++]; 
		
	} 
	
	//if(l!=left_size-1) 
	//{ 
		while(l <=left_size-1) A[++n] = left[l++]; 
	//} 
	//if (r!=right_size-1) 
	//{ 
		while(r <=right_size-1)A[++n] = right[r++]; 
	//} 
} 

void merge_sort(int a[],int first,int last) 
{ 
	int mid; 
	if (first <last) 
	{ 
		mid=(first+last)/2+1; 
		merge_sort(a,first,mid-1); 
		merge_sort(a,mid,last); 
		merge(a,first,mid,last); 
	} 
}
void main() 
{ 
	int a[ARRAY_SIZE]={846,4,78,46,12,547,54,47,33,51}; 
	merge_sort(a,0,9); 
	for (int i=0;i <10;i++) 
	{ 
		cout << a[i] <<endl; 
	} 
}