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

Difficulty: interview

Starter code:

Solutions:
# cook your dish here
try:
    t = int(input())
    for _ in range(t):
        p = [int(x) for x in input().split()]
        q = [int(x) for x in input().split()]
        
        q[1] *= -1
        m = (q[1]-p[1])/(q[0]-p[0])
        c = p[1] - m*p[0]
        
        print("{:.2f}".format(-c/m))
except:
    pass

#cook you dish here
t=int(input())
l=[]
for i in range(t):
    x1,y1=list(map(int,input().split()))
    x2,y2=list(map(int,input().split()))
    x=(x1*y2+x2*y1)/(y1+y2)
    l.append(x)
for i in l:
    print(i)
    



# cook your dish here
try:
    for _ in range(int(input())):
        x1,y1 = list(map(float,input().split()))
        x2,y2 = list(map(float,input().split()))
        
        result = (y1*x2 + y2*x1)/(y1+y2)
        print(result)
    
except Exception:
    pass


# cook your dish here
t=int(input())
while(t>0):
    x1,y1=input().split()
    x2,y2=input().split()
    x1=int(x1)
    x2=int(x2)
    y1=int(y1)
    y2=int(y2)
    x=min(x1,x2)
    if x==x1:
        ans=(y1*(x2-x1))/(y1+y2)
        ans=x1+ans
    else:
        ans=(y2*(x1-x2))/(y1+y2)
        ans=x2+ans
    print('%.2f'%ans)
    
    t=t-1

# cook your dish here
t=int(input())
l=[]
for i in range(t):
    x1,y1=list(map(int,input().split()))
    x2,y2=list(map(int,input().split()))
    x=(x1*y2+x2*y1)/(y1+y2)
    l.append(x)
for i in l:
    print(i)


for _ in range(int(input())):
	x1,y1=list(map(int,input().split()))
	x2,y2=list(map(int,input().split()))	
	m=(y2-(-y1))/(x2-x1)
	y=y2
	x=x2
	c=y-(m*x)

	y=0
	x=(y-c)/m
	print("{:.2f}".format(x))




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)

# cook your dish here
t=int(input())
for _ in range(t):
    x1,y1=map(int,input().split())
    x2,y2=map(int,input().split())
    ans=(y1*x2 + y2*x1)/(y1+y2)
    print("{0:.2f}".format(ans))