#include <stdio.h>
int getMax(int arr[], int n) {
int max = arr[0];
for (int i = 1; i < n; i++) {
if (arr[i] > max) {
max = arr[i];
}
}
return max;
}
void countingSort(int arr[], int n, int exp) {
const int MAX_DIGIT = 10;
int* output = (int*)malloc(n * sizeof(int));
int* count = (int*)malloc(MAX_DIGIT * sizeof(int));
if (output == NULL || count == NULL) {
printf("Memory allocation failed\n");
free(output);
free(count);
return;
}
for (int i = 0; i < MAX_DIGIT; i++) {
count[i] = 0;
}
for (int i = 0; i < n; i++) {
count[(arr[i] / exp) % MAX_DIGIT]++;
}
for (int i = 1; i < MAX_DIGIT; i++) {
count[i] += count[i - 1];
}
for (int i = n - 1; i >= 0; i--) {
output[count[(arr[i] / exp) % MAX_DIGIT] - 1] = arr[i];
count[(arr[i] / exp) % MAX_DIGIT]--;
}
for (int i = 0; i < n; i++) {
arr[i] = output[i];
}
free(output);
free(count);
}
void radixSort(int arr[], int n) {
int max = getMax(arr, n);
for (int exp = 1; max / exp > 0; exp *= 10) {
countingSort(arr, n, exp);
}
}
void printArray(int arr[], int size) {
for (int i = 0; i < size; i++) {
printf("%d ", arr[i]);
}
printf("\n");
}
int main() {
int arr[] = {170, 45, 75, 90, 802, 24, 2, 66};
int n = sizeof(arr) / sizeof(arr[0]);
printf("测试一:原始数组: ");
printArray(arr, n);
radixSort(arr, n);
printf("测试一:排序后数组: ");
printArray(arr, n);
int arr1[] = {39, 13, 100, 10, 1, 250};
int n1 = sizeof(arr1) / sizeof(arr1[0]);
printf("测试二:原始数组: ");
printArray(arr1, n1);
radixSort(arr1, n1);
printf("测试二:排序后数组: ");
printArray(arr1, n1);
int arr2[] = {99,111, 34, 23, 50, 88};
int n2 = sizeof(arr2) / sizeof(arr2[0]);
printf("测试二:原始数组: ");
printArray(arr2, n2);
radixSort(arr2, n2);
printf("测试二:排序后数组: ");
printArray(arr2, n2);
return 0;
}