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插值法查詢

#include <stdio.h>  
#include <time.h>  


#define SIZE 20  


void print_array(int a[], int len)  
{  
    int i = 0;  
    for (i = 0; i < len; i++){  
        printf("%d,", a[i]);  
    }  
    printf("\n");  
}  
void swap(int a[], int i, int j)  
{  
    int temp = a[i];  
    a[i] = a[j];  
    a[j] = temp;  
}  

void selection_sort(int
a[],int len) { int i = 0; int j = 0; for (i = 0; i < len; i++){ for (j = i; j < len;j++){ if (a[j] < a[i]){ swap(a,i,j); } } } } int binary_search_interpolation(int a[], int low, int high, int key) { int
ret = -1; while ((low <= high) && (a[low] <= key) && (key <= a[high])){ float fx = 1.0f * (key - a[low]) / (a[high] - a[low]); int mid = low + fx * (high - low); if (a[mid] == key){ ret = mid; break; } else
if (a[mid] > key){ high = mid - 1; } else{ low = mid + 1; } printf("%d\n", mid); } return ret; } int main(void){ int a[SIZE] = { 0 }; int i = 0; int key = 0; int index = -1; srand((unsigned int)time(NULL)); for (i = 0; i < SIZE; i++){ a[i] = rand() % 100; } key = rand() & 100; printf("Static Search Demo\n"); printf("Key: %d\n", key); printf("Array: \n"); print_array(a, SIZE); selection_sort(a,SIZE); print_array(a, SIZE); index = binary_search_interpolation(a, 0,SIZE, key); if (index >= 0){ printf("SUCCED: a[%d] = %d\n", index, a[index]); } else{ printf("Failed!!\n"); } system("PAUSE"); return 0; }