2020 is a special integer, it's formed of two same integers . We call a number is a good number, if and only if it can be formed of two same integers. For example: 2020 11, 19991999 are good numbers, but 303, 1122, 1221 are not. Now you need to count the number of good numbers in [1,N][1,N][1,N]
2020 is a special integer, it's formed of two same integers (20 and 20). We call a number is a good number, if and only if it can be formed of two same integers(without leading zero). For example: 2020 11, 19991999 are good numbers, but 303, 1122, 1221 are not. Now you need to count the number of good numbers in [1,N][1,N][1,N]
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