Problem Statement:
Given a, b and c, print the value of x according to the quadratic formula as shown in the image



Input Format:
three integer numbers a, b and c separated by single space


Output Format:
single number represents the value of x


Sample Input:
-3 -7 3


Sample Output:
-2.703257





Added by: gammal
Added at: 2015-02-02 19:14:15 UTC
Time Limit: 1 second
Partial score: No