/**
 * 給定二維陣列,尋找key值
 */

public class FindKey {

    public static  boolean findKey(int[][] arr,int key) {
        if (arr == null) {
            return false;
        }
        boolean flag = true;
        int column = arr[0].length-1;
        int row = 0;
        while (row < arr.length && column >= 0
 
) {
            if (arr[row][column] == key) {
                return true;
            } else if (arr[row][column] > key) {
                column--;
            } else {
                row++;
            }
        }
      return false;
    }public static void main(String[] args){
        int[][] arr=new int
 
[5][4];
        arr[0][0]=5;
        arr[0][1]=1;
        arr[0][2]=2;
        arr[0][3]=3;
        arr[1][0]=4;
        arr[1][1]=5;
        arr[1][2]=6;
        arr[1][3]=7;
        arr[2][0]=8;
        arr[2][1]=9;
        arr[2][2]=10;
        arr[2][3]=11;
        arr[3][0]=12;
        arr[3][1]=13;
        arr[3
 
][2]=14;
        arr[3][3]=15;
        arr[4][0]=16;
        arr[4][1]=17;
        arr[4][2]=18;
        arr[4][3]=10;
        System.out.println(findKey(arr,10));
    }
}