题解 | #筛选法求素数#

public class Program { public static void Main() { string input; while ((input = System.Console.ReadLine()) != null) { int len = int.Parse(input); int[] inPutNum = new int[len - 1]; //把数字装入数组 for (int i = 2; i <= len; i++) inPutNum[i - 2] = i;

        int clearNum = 0;
        //利用双循环去对比
        for (int i = 0; i < inPutNum.Length; i++) {
            for (int j = 1 + i; j < inPutNum.Length; j++) {
                if (inPutNum[i] != 0 && inPutNum[j] != 0) {
                    if (inPutNum[j] % inPutNum[i] == 0) {
                        inPutNum[j] = 0;
                        clearNum += 1;
                    } else {
                        continue;
                    }
                }
            }
        }

        //输出结果
        for (int i = 0; i < inPutNum.Length; i++)
            if (inPutNum[i] != 0)
                System.Console.Write(inPutNum[i] + " ");
        System.Console.WriteLine();
        //输出被清零的个数
        System.Console.WriteLine(clearNum);
    }
}

}