Find the remainder

Find the remainder when the digits 1 to 99 written side by side is divided by 11
i.e:
(123456789101112...99)mod 11=?
123456789101112.....979899
counting from right,
sum of digits at odd place = 9(9+8+...+1+0)+(9+7+5+3+1)
sum of digits at even place = 10(9+8+...+1)+(8+6+4+2)
sum of odd - sum of even = -40 = 4 (mod 11)


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