Vasya used to be an accountant before the war began and he is one of the few who knows how to operate a computer, so he was assigned as the programmer. We all know that programs often store sets of integers. For example, if we have a problem about a weighted directed graph, its edge can be represented by three integers: the number of the starting vertex, the number of the final vertex and the edge's weight. So, as Vasya was trying to represent characteristics of a recently invented robot in his program, he faced the following problem. Vasya is not a programmer, so he asked his friend Gena, what the convenient way to store n integers is. Gena used to code in language X- - and so he can use only the types that occur in this language. Let's define, what a "type" is in language X- -: First, a type is a string " int ". Second, a type is a string that starts with " pair ", then followed by angle brackets listing exactly two comma-separated other types of language X- -. This record contains no spaces. No other strings can be regarded as types. More formally: type := int | pair . For example, Gena uses the following type for graph edges: pair > . Gena was pleased to help Vasya, he dictated to Vasya a type of language X- -, that stores n integers. Unfortunately, Gena was in a hurry, so he omitted the punctuation. Now Gena has already left and Vasya can't find the correct punctuation, resulting in a type of language X- -, however hard he tries. Help Vasya and add the punctuation marks so as to receive the valid type of language X- -. Otherwise say that the task is impossible to perform. The first line contains a single integer n (1 ≤ n ≤ 10 5 ) , showing how many numbers the type dictated by Gena contains. The second line contains space-separated words, said by Gena. Each of them is either " pair " or " int " (without the quotes). It is guaranteed that the total number of words does not exceed 10 5 and that among all the words that Gena said, there are exactly n wor