基数排序

#include<iostream>
#include<ctime>
#include<cstdlib>
#include<cassert>
#include<cmath>
#include<iomanip>

using namespace std;

int **bu;

int power(int x,int y)
{
if( y == 0)
return 1;

int i;
int sum = 1;
for(i=0;i<y;++i)
{
sum *= x;
}
return sum;
}

void BucketSort(int a[],int n)
{
int pass = 0;
do
{
int i,j;
for(i=0;i<10;++i)
{
bu[i][n] = 0;
}
for(i=0;i<n;++i)
{
int t1 = power(10,pass);
int t2 = a[i] / t1 % 10;
bu[t2][bu[t2][n]++] = a[i];
}
int k = 0;
for(i=0;i<10;++i)

{
for(j=0;j<bu[i][n];++j)
{
a[k++] = bu[i][j];
}
}
++pass;
}while(bu[0][n] != n);

}


int main()
{
int n;
cout<<"Please input the number of datas."<<endl;
cin>>n;

assert(n>0);
bu = new int *[10];
int i;
int *a = new int[n];
srand(time(0));
cout<<"Before sort!"<<endl;
for(i=0;i<10;++i)
{
bu[i] = new int [n+1];
}

for(i=0;i<n;++i)
{
a[i] = rand()%1000+1;
cout<<setw(5)<<a[i];
}
cout<<endl;
cout<<"After sort."<<endl;

BucketSort(a,n);
for(i=0;i<n;++i)
{
cout<<setw(5)<<a[i];
}
cout<<endl;

for(i=0;i<n;++i)
{
delete []bu[i];
}
delete []bu;
system("pause");
return 0;
}