Tiger's leetcode solution: hackRand problem

Tiger's leetcode solution: hackRand problem
检测一个2D数组  其 x，y坐标的k范围内是否存在重复

    public static void main(String args[] ) throws Exception {

 

        Scanner sc = new Scanner(System.in);

        int n = sc.nextInt();

 

        if(n<=0){System.out.print("NO"); return;}

        String str  = sc.nextLine();

        // change str into line

        List<Integer[]> list = new LinkedList();

 

        int[][] Arr = new int[n][n];

 

        for(int i =0;i<n;i++) {

            String strArr[] = sc.nextLine().split("\\s+");

            for (int j = 0; j < strArr.length; j++)

                Arr[i][j] = Integer.parseInt(strArr[j]);

        }

 

        int k = sc.nextInt();

        int m = Arr[0].length;

 

 

        Map<Integer,Integer> map = new HashMap();

 

        //  each position as a center, and find it int the circle/ use k as radius

        for(int i =0;i<n;i++) {

            map.clear();

            // set-up the circle into the map

            for(int row=0; row < Math.min(n,i+k+1);row++){

                for(int col = 0;col<Math.min(n,k+1);col++){

                    if(row == i && col == 0)

                        continue;

                    int key = Arr[row][col];

                    addMap(map, key);

                }

            }

            // mvoe for each i-th position

            for (int j = 0; j < Arr[0].length; j++) {   // not, current i,j is not included

                int val = Arr[i][j];

                if(map.containsKey(val)){

                    System.out.println("YES");

                    return;

                }

                map.put(val,1);

                // remove most left column and add most left row

                if(j+ 1< m)

                    delMap(map,Arr[i][j+1]);

                if( j - k >=0 ){ // delete this 2k column

                    for(int row=Math.max(0,i-k); row < Math.min(n,i+k+1);row++){

                        delMap(map, Arr[row][j-k]);

                    }

                }

                if( j + k +1 < m ){ // add this 2k column

                    for(int row=Math.max(0,i-k); row < Math.min(n,i+k+1);row++){

                        addMap(map, Arr[row][j + k + 1]);

                    }

                }

 

            }

        }

 

        System.out.println("NO");

    }

 

    private static void addMap(Map<Integer,Integer> map, int val){

        int count = 0;

        if(map.containsKey(val))

            count = map.get(val);

        map.put(val,count+1);

    }

    private static void delMap(Map<Integer,Integer> map, int val){

        if(map.containsKey(val)) {

            int count = map.get(val);

            if(count==1){

                map.remove(val);

            }else

                map.put(val, count - 1);

        }

    }

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