A universal binary lookup algorithm based on C language

/* Binary lookup is an algorithm based on good order.
	
	The complexity is low, and very efficient, because the project in a large number of use of two-point lookup, but not each business implementation of one so it is necessary to implement a common binary search its main idea: through the ordered array, the data pointer comparison. @const void *key need to find the key value @const void *base, the first address to find the data @int Nmemb, the number of members to find @int size, the size of each element @int *piequal, whether it can be found The flag is found to be 1, otherwise 0 */int bsearch_int (const void *key, const void *base, int nmemb, int size, int *piequal) {size_t L, u, id
	X
	const void *p, *P2;


	int comparison, Comparison2;
	*piequal = 0;
	if (Nmemb < 0) return-1;
	if (!NMEMB) return 0;
	L = 0;


	u = nmemb;
		while (L < u) {idx = (l + u)/2;
		p = (void *) ((const char *) base) + (IDX * size));


		comparison = * (int *) Key-* (int *) p;
			if (comparison = = 0) {*piequal = 1;
		return idx;


			else if (comparison < 0) {if (idx = 0) return idx;
			P2 = (void *) ((const char *) base) + ((idx-1) * size));


			Comparison2 = * (int *) Key-* (int *) P2;


			if (Comparison2 > 0) return idx;
		u = idx;
		else/*if (Comparison > 0) */{L = idx + 1;	}	
	return u; }

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