import collections
import heapq
a, b = input().split(" ")
n, k = int(a), int(b)
def f(n,k):
return 2*n+1+min(k-1,n-k)+n-1
print(f(n,k))
1618A - Polycarp and Sums of Subsequences | 1618B - Missing Bigram |
938. Range Sum of BST | 147. Insertion Sort List |
310. Minimum Height Trees | 2110. Number of Smooth Descent Periods of a Stock |
2109. Adding Spaces to a String | 2108. Find First Palindromic String in the Array |
394. Decode String | 902. Numbers At Most N Given Digit Set |
221. Maximal Square | 1200. Minimum Absolute Difference |
1619B - Squares and Cubes | 1619A - Square String |
1629B - GCD Arrays | 1629A - Download More RAM |
1629C - Meximum Array | 1629D - Peculiar Movie Preferences |
1629E - Grid Xor | 1629F1 - Game on Sum (Easy Version) |
2148. Count Elements With Strictly Smaller and Greater Elements | 2149. Rearrange Array Elements by Sign |
2150. Find All Lonely Numbers in the Array | 2151. Maximum Good People Based on Statements |
2144. Minimum Cost of Buying Candies With Discount | Non empty subsets |
1630A - And Matching | 1630B - Range and Partition |
1630C - Paint the Middle | 1630D - Flipping Range |