CF257D.Sum

普及/提高-

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题目描述

Vasya has found a piece of paper with an array written on it. The array consists of nn integers a1,a2,...,ana_{1},a_{2},...,a_{n} . Vasya noticed that the following condition holds for the array ai<=ai+1<=2aia_{i}<=a_{i+1}<=2·a_{i} for any positive integer ii ( i<n ).

Vasya wants to add either a "+" or a "-" before each number of array. Thus, Vasya will get an expression consisting of nn summands. The value of the resulting expression is the sum of all its elements. The task is to add signs "+" and "-" before each number so that the value of expression ss meets the limits 0<=s<=a10<=s<=a_{1} . Print a sequence of signs "+" and "-", satisfying the given limits. It is guaranteed that the solution for the problem exists.

输入格式

The first line contains integer nn ( 1<=n<=1051<=n<=10^{5} ) — the size of the array. The second line contains space-separated integers a1,a2,...,ana_{1},a_{2},...,a_{n} ( 0<=ai<=1090<=a_{i}<=10^{9} ) — the original array.

It is guaranteed that the condition ai<=ai+1<=2aia_{i}<=a_{i+1}<=2·a_{i} fulfills for any positive integer ii ( i<n ).

输出格式

In a single line print the sequence of nn characters "+" and "-", where the ii -th character is the sign that is placed in front of number aia_{i} . The value of the resulting expression ss must fit into the limits 0<=s<=a10<=s<=a_{1} . If there are multiple solutions, you are allowed to print any of them.

输入输出样例

  • 输入#1

    4
    1 2 3 5
    

    输出#1

    +++-
  • 输入#2

    3
    3 3 5
    

    输出#2

    ++-
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