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84 lines
2.6 KiB
C
84 lines
2.6 KiB
C
/*********************************************************************************************************
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* ------------------------------------------------------------------------------------------------------
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* file description
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* ------------------------------------------------------------------------------------------------------
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* \file search.h
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* \unit search
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* \brief This is a C language version of commonly used search algorithms
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* \author Lamdonn
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* \version v1.0.0
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* \license GPL-2.0
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* \copyright Copyright (C) 2023 Lamdonn.
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********************************************************************************************************/
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#include "search.h"
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int search_linear(void *array, int left, int right, void *target, SearchOPS *ops)
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{
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int i;
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/* Check the validity of input parameters */
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if (!array) return -1;
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if (left > right || right < 0) return -1; // If the left and right boundaries are invalid, return -1
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if (!target) return -1;
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if (!ops) return -1;
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/* Traverse the specified range of an array */
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for (i = left; i <= right; i++)
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{
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/* Compare the current element with the target element using the provided comparison function */
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if (ops->cmp(ops->addr(array, i), target) == 0)
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{
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return i;
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}
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}
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return -1;
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}
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static int search_binary_s(void *array, int left, int right, int r, void *target, SearchOPS *ops)
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{
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int c = 0;
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int mid = left + (right - left) / 2;
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/* There is an error on the left and right boundaries, and the search has failed */
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if (left > right) return -1;
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/* Obtain comparison results */
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c = ops->cmp(ops->addr(array, mid), target) * r;
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/* According to the comparison results, search in segments */
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if (c == 0)
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{
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return mid;
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}
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else if (c > 0)
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{
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/* Search for the left interval */
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return search_binary_s(array, left, mid - 1, r, target, ops);
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}
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else
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{
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/* Search for the right interval */
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return search_binary_s(array, mid + 1, right, r, target, ops);
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}
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}
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int search_binary(void *array, int left, int right, void *target, SearchOPS *ops)
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{
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int r = 0;
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/* Check the validity of input parameters */
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if (!array) return -1;
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if (left > right || right < 0) return -1;
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if (!target) return -1;
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if (!ops) return -1;
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/* Get the current sorting rule */
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r = -ops->cmp(ops->addr(array, left), ops->addr(array, right));
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/* Return binary search results */
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return search_binary_s(array, left, right, r, target, ops);
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}
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