public static String printOptimal1(int[][] root,int i ,int j ){
		if (i == j) {
			return ("K"+i);
		}else if (j==i-1) {
			return ("d"+j);
		}else if (i==j+1) {
			return ("d"+i);
		}else {
			System.out.println("K"+root[i][j]+"Ϊ"+printOptimal(root, i, root[i][j]-1));
			//printOptimal(root, i, root[i][j]-1);
			//System.out.println();
			System.out.print("K"+root[i][j]+"Ϊ"+printOptimal(root, root[i][j]+1,j));
			//printOptimal(root, root[i][j]+1,j);
			//System.out.println();
		}
		return "";
	}