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QOJ

Time Limit: 1.0 s Memory Limit: 256 MB Total points: 100

#18659. 靚嘅和

Statistics

靚嘅和係幾個連續正整數相加得出嘅和。例如,$7 + 8$ 同 $4 + 5 + 6$ 都係靚嘅和,而 $3 + 5 + 7$ 就唔係,雖然佢哋嘅值全部都等於 $15$。(只有一個加數 $15$ 嘅和亦算係靚嘅和。)

因此,一個整數嘅靚度指數,就係將佢表示成靚嘅和嘅方法數。例如,數字 $15$ 嘅靚度指數等於 $4$,因為 $15$ 可以用四種方法表示成靚嘅和:$15 = 7 + 8 = 4 + 5 + 6 = 1 + 2 + 3 + 4 + 5$。

如果一個數嘅靚度指數較高,就認為佢比另一個數更靚。如果兩個數嘅靚度指數相同,就認為較細嗰個數更靚。例如,$15$ 係靚度指數為 $4$ 嘅最細整數。

你要搵出靚度指數等於畀定嘅 $n$ 嘅最細整數。

輸入格式

唯一一行有一個整數 $n$($1 \le n \le 10^5$)。

輸出格式

輸出靚度指數等於畀定嘅 $n$ 嘅最細整數對 $(10^9 + 9)$ 取模嘅結果。

例子

輸入格式 1

3

輸出格式 1

9

輸入格式 2

4

輸出格式 2

15

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