牛骨文教育服务平台(让学习变的简单)
#include <iostream>
using namespace std;

int count = 0;

void merge(int *a,int p,int q,int r){
	int n1 = q-p+1;
	int n2 = r-q;
	int *m = new int[n1];
	int *n = new int[n2];
	for(int i=0;i<n1;i++) m[i] = a[p+i];
	for(int j=0;j<n2;j++) n[j] = a[q+j+1];
	int i=0,j=0,k=p;
	while(i<n1&&j<n2){
		if(m[i]<=n[j]) a[k++] = m[i++];
		else {
			int ni = q + 1 + j - k;
			count += ni;
			a[k++] = n[j++];
		}
	}
	while(i<n1) a[k++] = m[i++];
	while(j<n2) a[k++] = n[j++];
	delete[] m,n;
}
void mergeSort(int *a,int p,int r){
	if(p<r){
		int q = (p+r)/2;
		mergeSort(a,p,q);
		mergeSort(a,q+1,r);
		merge(a,p,q,r);
	}
}

int main(int argc, char** argv) {
	int a[10] = {9,8,7,6,5,4,3,2,1,0};
	mergeSort(a,0,9);
	for(int i=0;i<10;i++)
		cout<<a[i];
	cout<<endl<<count<<endl;
	return 0;
}