public class sequenceQuery {
	/* 对于无序表的搜索 顺序搜索*/
	public int seqSearch(int[] datalist, int target) {
		for (int i = 0; i < datalist.length; i++) {
			if (datalist[i] == target)
				return i;
		}
		return -1;
	}

	/* 二叉搜索，对于有序表 */
	public int binarySearch(int[] datalist, int target) {
		int mid = 0;
		int first = 0;
		int last = datalist.length - 1;

		while (first <= last) {
			mid = (first + last) / 2;
			if (target == datalist[mid])
				return mid;
			else {
				if (target > datalist[mid])
					first = mid + 1;
				else
					last = mid - 1;
			}
		}
		return -1;
	}

	public static void main(String[] args) {
		int datalist1[] = { 23, 566, 89, 0, 2, 7, 90, 34, 12, 744, 3257 };
		int datalist2[] = { 23, 28, 89, 100, 200, 778, 902, 1234, 1724, 7442,32257 };
		sequenceQuery s = new sequenceQuery();
		System.out.println(s.seqSearch(datalist1, 90));
		System.out.println(s.binarySearch(datalist2, 902));
	}
}

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