Little Frog

### 题目描述 从前一个名叫 Vasya 的小青蛙决定在它家的沼泽里四处旅行。沼泽里有 $n$ 个位于一条线的土堆，相邻的土堆之间的距离是 $1$ 米。Vasya 想在一天内参观所有的土堆；此外，它想每一个都只去一次。为此，它制定了一个路线计划。Vasya 可以选择任何土丘作为起点。同时，它想要任何两次跳跃的路径的长度不同。请你帮助 Vasya 青蛙，完成它的计划。 ### 输入格式 输入一个正整数 $n(1\le n\le10^4)$，即土堆的数量。 ### 输出格式 输出 $n$ 个正整数 $p_i$（要求$1\le p_i\le n$），表示小青蛙第 $i$ 次跳到第 $p_i$ 个土丘上。如果有多种解决方案，输出任何一个即可。

Once upon a time a little frog whose name was Vasya decided to travel around his home swamp. Overall there are $ n $ mounds on the swamp, located on one line. The distance between the neighboring mounds is one meter. Vasya wants to visit all the mounds in one day; besides, he wants to visit each one exactly once. For that he makes a route plan, to decide the order in which to jump on the mounds. Vasya can pick any mound as the first one. He thinks it boring to jump two times at the same distance. That's why he wants any two jumps on his route to have different lengths. Help Vasya the Frog and make the plan for him.

The single line contains a number $ n $ ( $ 1<=n<=10^{4} $ ) which is the number of mounds.

Print $ n $ integers $ p_{i} $ ( $ 1<=p_{i}<=n $ ) which are the frog's route plan. - All the $ p_{i} $ 's should be mutually different. - All the $ |p_{i}–p_{i+1}| $ 's should be mutually different ( $ 1<=i<=n-1 $ ). If there are several solutions, output any.

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