二维数组查找

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package array;

public class SearchIn2DArray {

    public static boolean Find(int target, int[][] array) {
        int num = FindBySecond(array[0], 0, array[0].length - 1, target, 1);

        if (num < 0) {
            return false;
        }
        int[] find_arrray = searchArray(array, num);
        int position = FindBySecond(find_arrray, 0, find_arrray.length - 1, target, 2);
        if (position >= 0) {
            return true;
        } else {
            while (num >= 0) {
                int[] find_arrray_new = searchArray(array, num);
                int position2 = FindBySecond(find_arrray_new, 0, find_arrray_new.length - 1, target, 2);
                if (position2 >= 0) {
                    return true;
                }
                num--;
            }
            return false;
        }
    }

    public static int[] searchArray(int[][] array, int col) {
        int[] find_arrray = new int[array.length];
        for (int i = 0; i < array.length; i++) {
            find_arrray[i] = array[i][col];
        }
        return find_arrray;
    }

    // 二分查找
    public static Integer FindBySecond(int[] array, int left, int right, int key, int time) {
        if (left > right) {
            if (time == 1) return right;
            else return -1;
        }
        int middle = left + (right - left) / 2;
        if (key < array[middle]) return FindBySecond(array, left, middle - 1, key, time);
        if (key == array[middle]) {
            return middle;
        } else return FindBySecond(array, middle + 1, right, key, time);
    }

    public static void main(String[] args) {

        int[][] array = {
                {1, 2, 4, 6, 8, 10, 11, 13, 15, 17, 20, 22, 24, 27, 30, 32, 35, 36, 38, 39, 42, 44, 46, 47, 48, 49, 51, 54, 55, 56},
                {3, 4, 6, 8, 11, 13, 15, 18, 19, 20, 23, 25, 27, 29, 33, 36, 38, 41, 42, 45, 48, 50, 53, 54, 57, 60, 63, 65, 66, 67},
                {5, 7, 8, 11, 14, 15, 17, 19, 21, 23, 24, 28, 31, 33, 36, 39, 41, 44, 47, 49, 52, 53, 56, 57, 60, 63, 66, 68, 71, 72},
                {7, 10, 13, 14, 17, 19, 22, 25, 26, 27, 30, 32, 34, 37, 39, 42, 44, 46, 50, 53, 55, 56, 59, 61, 64, 66, 69, 72, 74, 76},
                {8, 12, 16, 17, 20, 21, 23, 26, 29, 31, 33, 35, 37, 40, 42, 45, 48, 49, 52, 55, 58, 59, 61, 63, 67, 69, 70, 74, 76, 79},
                {10, 15, 18, 20, 22, 24, 27, 30, 32, 33, 36, 38, 39, 41, 45, 47, 50, 53, 56, 58, 61, 64, 65, 68, 69, 71, 73, 76, 79, 82},
                {13, 17, 20, 23, 24, 26, 28, 31, 34, 36, 38, 41, 42, 43, 48, 50, 53, 56, 58, 61, 64, 67, 68, 71, 73, 74, 75, 78, 81, 84},
                {15, 19, 22, 24, 26, 28, 31, 34, 35, 38, 41, 44, 45, 46, 49, 51, 56, 59, 61, 64, 67, 69, 71, 73, 76, 78, 79, 82, 85, 87},
                {17, 20, 23, 26, 29, 30, 32, 37, 40, 42, 43, 47, 50, 53, 55, 56, 58, 62, 64, 66, 69, 72, 75, 78, 80, 81, 83, 86, 88, 90},
                {18, 21, 25, 28, 30, 32, 35, 38, 42, 43, 44, 49, 51, 55, 58, 59, 61, 65, 68, 71, 73, 74, 77, 79, 82, 85, 88, 89, 91, 93},
                {20, 23, 28, 29, 33, 36, 37, 40, 43, 45, 47, 52, 55, 58, 60, 62, 63, 66, 70, 74, 76, 77, 79, 81, 85, 88, 89, 91, 93, 94},
                {23, 25, 31, 33, 35, 39, 42, 43, 44, 46, 50, 53, 56, 61, 62, 65, 68, 69, 72, 75, 78, 81, 82, 83, 88, 91, 92, 93, 96, 99},
                {26, 27, 33, 34, 38, 40, 45, 48, 51, 53, 55, 56, 58, 64, 66, 69, 72, 75, 77, 80, 82, 84, 87, 88, 90, 93, 94, 95, 99, 101},
                {29, 30, 36, 38, 40, 42, 47, 50, 53, 56, 57, 59, 62, 65, 68, 71, 73, 77, 79, 83, 84, 86, 88, 91, 93, 96, 99, 100, 102, 103},
                {32, 33, 39, 42, 44, 46, 49, 53, 56, 59, 62, 65, 68, 71, 72, 75, 77, 78, 80, 85, 87, 90, 92, 94, 96, 99, 101, 103, 105, 107},
                {35, 37, 42, 43, 46, 48, 51, 55, 59, 61, 65, 67, 71, 74, 76, 78, 81, 82, 84, 86, 90, 92, 95, 96, 99, 102, 103, 106, 107, 109},
                {36, 39, 43, 46, 49, 50, 53, 58, 62, 65, 67, 70, 73, 76, 77, 79, 84, 87, 88, 90, 93, 96, 99, 102, 103, 106, 108, 111, 112, 115},
                {38, 42, 45, 47, 52, 55, 57, 60, 64, 66, 69, 72, 75, 78, 80, 82, 87, 89, 91, 92, 94, 99, 100, 103, 105, 107, 111, 112, 115, 118},
                {39, 44, 48, 49, 55, 57, 60, 63, 66, 69, 72, 75, 78, 80, 82, 85, 89, 92, 94, 95, 98, 101, 102, 105, 108, 111, 112, 115, 116, 120},
                {40, 47, 49, 52, 56, 59, 63, 64, 68, 71, 75, 78, 80, 83, 85, 88, 91, 94, 97, 99, 101, 104, 105, 108, 110, 112, 115, 118, 120, 123},
                {42, 50, 53, 55, 59, 62, 66, 67, 71, 73, 78, 81, 82, 86, 87, 90, 94, 97, 100, 101, 104, 106, 107, 109, 111, 114, 117, 120, 123, 126},
                {43, 51, 55, 58, 62, 64, 69, 71, 74, 77, 81, 84, 86, 87, 89, 93, 96, 99, 102, 103, 105, 108, 111, 112, 113, 116, 120, 122, 125, 129},
                {45, 54, 56, 59, 65, 67, 72, 75, 76, 79, 84, 87, 90, 92, 94, 97, 99, 102, 104, 107, 108, 111, 114, 116, 119, 120, 122, 124, 127, 132}};

        System.out.println(Find(102, array));
    }
}