Kabir likes Tara's smile and wants to look at her smile. They are sitting in the class and you are friends with Kabir. You have to place a mirror (point size)  in the front wall of the class so that Kabir can have a glimpse of Tara's smile.
Consider the front wall as x-axis . You are given the  coordinates of position of Kabir (x1,y1)$(x1,y1)$ and Tara  (x2,y2)$(x2,y2)$. Find the position where the mirror should be placed. 
-----Input:-----
- First line will contain T$T$, number of testcases. Then the testcases follow. 
- First line of each testcase contains two integers x1,y1$x1, y1$.
- Second line of each testcase contains two integers x2,y2$x2, y2$. 
-----Output:-----
For each testcase, print the x-coordinate of the mirror. Absolute error of 10−2$10^{−2}$ is allowed.
-----Constraints:-----
- 1≤T≤1000$1 \leq T \leq 1000$
- 1≤x1,y1,x2,y2≤105$1 \leq x1,y1,x2,y2 \leq 10^5 $
-----Sample Input:-----
1
1 1
4 4
-----Sample Output:-----
1.60
n=int(input())
for i in range(n):
    x1,y1=map(int,input().split())
    x2,y2=map(int,input().split())
    if(x1>x2):
        t=x1
        x1=x2
        x2=t
        t1=y1
        y1=y2
        y2=t1
    r=y1*(x2-x1)
    r1=r/(y2+y1)
    print(x1+r1)
n=int(input())
for i in range(n):
    x1,y1=map(int,input().split())
    x2,y2=map(int,input().split())
    if(x1>x2):
        t=x1
        x1=x2
        x2=t
        t1=y1
        y1=y2
        y2=t1
    r=y1*(x2-x1)
    r1=r/(y2+y1)
    print(x1+r1)