Polynomial
Some polynomial is represented as a product of first-degree binomials of the form (x + a[1] ) * (x + a[2]) * ... * (x + a[n]). Print this polynomial in standard form x^n + b[1] * x^(n-1) + ... + b[n-1] * x + b[n]. Moreover, c * x^k is printed as c * x^k (for example 5 * x^8), but if coefficient c equals to 0, the term is not printed, if |c| equals to 1, and k > 0, then the sign of coefficient c is printed only (for example -x^3). If k = 1, the degree is not printed (for example 5 * x), if k = 0, print only c. The terms should be printed in decreasing order of the multiplier x^k.
Input
The first line contains the number of binomials n (1 ≤ n ≤ 9), each of the next n lines contains one integer from -10 to 10 - the coefficients a[i] of multiplied binomials.
Output
Print the polynomial in the specified standard form. As X, an uppercase Latin letter is used.