Problem:
Score : 100 points

Problem Statement

There is an N-car train.

You are given an integer i. Find the value of j such that the following statement is true: "the i-th car from the front of the train is the j-th car from the back."

Constraints

1 \leq N \leq 100

1 \leq i \leq N

Input

Input is given from Standard Input in the following format:

N i

Output

Print the answer.

Sample Input 1

4 2

Sample Output 1

3

The second car from the front of a 4-car train is the third car from the back.

Sample Input 2

1 1

Sample Output 2

1

Sample Input 3

15 11

Sample Output 3

5

Solution in Ruby (2.3.3) (judge verdict: Runtime Error)

h, w = gets.split.map(&:to_i)
hs = []
h.times{ hs << gets.chomp.split("") }
def del_same_line(target_ary)
  target_ary.reject{|e| !e.include?('#') }.transpose
end
del_same_line(del_same_line(hs)).each{|e| puts e.inject(:+)}