int []arr=new int{8,2,1,0,3}; int[]index=new int{2,0,3,2,40,1,3,2,3,3}; for(int I:index){string t+=arr[i]; system.out.println(t); }
循环index,取出元素i,例如2,然后到arry里面拿第二个元素加到t里面,然后打印t,