Help me in solving LB19 problem

My issue

Chef has made a list for his monthly expenses. The list has

N expenses with index
1
1 to

N. The money spent on each expense depends upon the monthly income of Chef.

Chef spends
50
%
50% of his total income on the expense with index
1
1.
The money spent on the



i
th
expense
(

1
)
(i>1) is equal to
50
%
50% of the amount remaining, after paying for all expenses with indices less than

i.
Given that Chef earns
2

2
X
rupees in a month, find the amount he saves after paying for all

N expenses.

Input Format
The first line of input will contain a single integer

T, denoting the number of test cases.
Each test case consists of two space-separated integers

N and

X — where

N denotes the number of expenses and
2

2
X
denotes the monthly income of Chef.
Output Format
For each test case, output on a new line, the amount saved by Chef after paying for all

N expenses.

Constraints
1



1000
1≤T≤1000
1


<


20
1≤N<X≤20
Sample 1:
Input
Output
4
1 2
1 3
2 3
3 4
2
4
2
2

My code

# Update the code below to solve this problem

t = int(input())
for i in range(t):
    N, X = map(int, input().split())

Learning course: Python with Data structures
Problem Link: Review problem - 3 Practice Problem in Python with Data structures - CodeChef