基数排序

 

#include<iostream>
#include<string>
using namespace std;
//数值型基数排序
int getDigit(int num, int index)
{
    int mod = 1;
    while (index)
    {
        mod *= 10;
        index--;
    }
    int div = mod / 10;
    return num%mod / div;

}

void Count_Sort(int *A, int *B, int len, int k,int d)
{
    int count = k + 1;
    int *C = new int[count];
    for (int i = 0; i < count; i++)
    {
        C[i] = 0;
    }
    for (int i = 0; i < len; i++)
    {
        C[getDigit(A[i], d)] = C[getDigit(A[i], d)] + 1;
    }
    for (int i = 1; i < count; i++)
        C[i] = C[i] + C[i - 1];
    for (int i = len-1; i >=0; i--)
    {
        B[C[getDigit(A[i], d)] - 1] = A[i];
        C[getDigit(A[i], d)] = C[getDigit(A[i], d)] - 1;
    }
}
void RADIX_SORT(int *A, int d,int len)
{
    for (int i = 1; i <=d; i++)
    {
        int *B = new int[len];
        Count_Sort(A, B, len, 10,i);
        for (int i = 0; i < len; i++)
        {
            A[i] = B[i];
        }
    }
}
//字符型基数排序
int getAlpha(string A, int index)
{
    return (A[A.length()-index]-'a');
}
void Count_SortAlpha(string*A, string*B, int len, char k, int d)
{
    int count = (k-'a' + 1);
    int *C = new int[count];
    for (int i = 0; i < count; i++)
    {
        C[i] = 0;
    }
    for (int i = 0; i < len; i++)
    {
        C[getAlpha(A[i], d)] = C[getAlpha(A[i], d)] + 1;
    }
    for (int i = 1; i < count; i++)
        C[i] = C[i] + C[i - 1];
    for (int i = len - 1; i >= 0; i--)
    {
        B[C[getAlpha(A[i], d)]-1 ] = A[i];
        C[getAlpha(A[i], d)] = C[getAlpha(A[i], d)] - 1;
    }
}
void RADIX_SORTAlpha(string A[], const int d, const int len)
{
    for (int i = 1; i <= d; i++)
    {
        string *B=new string[len];
        Count_SortAlpha(A, B, len, 'z', i);
        for (int i = 0; i < len; i++)
        {
            A[i] = B[i];
        }
        delete[] B;
    }
}

int main()
{

    
        int A[] = { 329,457,657,839,436,720,355,0,12,15,105 };     
        int N = sizeof A / sizeof A[0];
        RADIX_SORT(A, 3, N);
        for (int i = 0; i<N; i++)
        {
            cout << A[i] << "  ";
        }
        cout << "
";

        string Alpha[] = { "cow", "sea", "rug", "row","mob","box","tab","bar","tar","dig","big","tea","now","fox" };

        N = sizeof Alpha / sizeof Alpha[0];
        RADIX_SORTAlpha(Alpha, 3, N);
        for (int i = 0; i < N; i++)
        {
            cout << Alpha[i] << "  ";
        }
        cout << "
";

        return 0;
    


}