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如何使用基數排序對數組中的某些浮點數據進行排序? 我認爲我應該把所有數據乘以10的最小冪,這使它們成爲整數。但我不知道我怎麼能理解這種合適的力量。 這是用於排序整數數組的C++代碼。 有人可以幫我做這個嗎?如何使用基數排序來計算浮點數的數組?
#include<iostream>
using namespace std;
//Get maximum value in arr[]
int findMax(int arr[], int n)
{
int max = arr[0];
for (int i = 1; i < n; i++)
if (arr[i] > max)
max = arr[i];
return max;
}
// A function to do counting sort of arr[] according to
// the digit represented by exp.
void countSort(int arr[], int n, int exp)
{
int outputArr[n]; // output array
int i, count[10] = {0};
// Store count of occurrences in count[]
for (i = 0; i < n; i++)
count[ (arr[i]/exp)%10 ]++;
// Change count[i] so that count[i] now contains actual
// position of this digit in output[]
for (i = 1; i < 10; i++)
count[i] += count[i - 1];
// Build the output array
for (i = n - 1; i >= 0; i--)
{
outputArr[count[ (arr[i]/exp)%10 ] - 1] = arr[i];
count[ (arr[i]/exp)%10 ]--;
}
// Copy the output array to arr[], so that arr[] now
// contains sorted numbers according to current digit
for (i = 0; i < n; i++)
arr[i] = outputArr[i];
}
// The main function to that sorts arr[] of size n using Radix Sort
void radixsort(int arr[], int n)
{
int max = findMax(arr, n);
// Do counting sort for every digit. Note that instead
// of passing digit number, exp is passed. exp is 10^i
// where i is current digit number
for (int exp = 1; max/exp > 0; exp *= 10)
countSort(arr, n, exp);
}
// A utility function to print an array
void print(int arr[], int n)
{
for (int i = 0; i < n; i++)
cout << arr[i] << " ";
}
int main()
{
int arr[] = {506,2,41,33,5,965,73};
int n = sizeof(arr)/sizeof(arr[0]);
radixsort(arr, n);
print(arr, n);
return 0;
}
這是通用的,還是隻爲IEEE浮動?另外,NAN和其他特殊值會發生什麼?最後,這是否正確地處理非規範化的數字? –
@JimMischel - 此方法適用於IEEE浮點數,特別是符號和數量級的浮點數。非規範化數字應該可以正常工作。取決於指數值,特殊值將被排序到前面或後面。 – rcgldr