public static int[][] Func(int[][] arr, int m, int n) {
        int min=arr[0][0];
        int minindex=0;
        int max=arr[0][0];
        int maxindex=0;
        int x;
        for (int i = 0; i < m; i++)
        {
            for (int j = 0; j < n; j++)
            {
                if (arr[i][j]<min) {
                    min = arr[i][j];
                    minindex = j;
                }
                if (arr[i][j]>max) {
                    max = arr[i][j];
                    maxindex = j;
                }
            }
        }
        for (int i = 0; i < m; i++)
        {
            x =arr[i][minindex];
            arr[i][minindex]=arr[i][maxindex];
            arr[i][maxindex]=x;
        }
        return arr;
    }