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: Accepted)

# util functions

# debug
$debugFlag = ( ARGV[0] != nil )
p "==== DEBUG MODE ====" if $debugFlag

def pd(str)
  p str if $debugFlag
end

def printd(str)
  print str if $debugFlag
end

# input
inputs = []
lc = 0
while l = $stdin.gets do
  if false
    inputs << l.chomp.split(" ").map(&:to_s)
  else
    inputs << l.chomp.split(" ").map(&:to_i)
  end
  lc += 1
end

nn = inputs[0][0]
ii = inputs[0][1]

# input check
if $debugFlag
  p "--- INPUT (begin) ---"
  inputs.each do |l_i|
    p l_i
  end
  p "--- INPUT (end) ---"
  print "\n"
end

# body
if $debugFlag
  p nn
  p ii
end

puts nn - ii + 1