There is a series of numbers written on the blackboard: 1, 2, 3, ..., 2011, 2012, erase a few numbers arbitrarily, and write the remainder of the sum of the erased numbers divided by 11, such as: erase 8 , 9, 10, 11, 12, because (8+9+10+11+12)/11=4...6, so write 6, and continue this operation until there is only one number left on the blackboard, then this number how many.
黑板上写有一串数：1、2、3、…、2011、2012，任意擦去几个数，并写上被擦去的几个数的和被11除所得的余数，如：擦去8、9、10、11、12，因为(8+9+10+11+12)/11=4…6，于是写上6，这样操作下去，一直到黑板上只剩下一个数，则这个数是多少．
<result>0</result>