n=int(input())
res=0
f=[0]*2010
for i in range(n):
opt=input().split()
s,c=opt[0],int(opt[1])
if s=="win":
f[c]=res+2**c
else:
res=max(res,f[c])
print(res)1550A - Find The Array | 118B - Present from Lena |
27A - Next Test | 785. Is Graph Bipartite |
90. Subsets II | 1560A - Dislike of Threes |
36. Valid Sudoku | 557. Reverse Words in a String III |
566. Reshape the Matrix | 167. Two Sum II - Input array is sorted |
387. First Unique Character in a String | 383. Ransom Note |
242. Valid Anagram | 141. Linked List Cycle |
21. Merge Two Sorted Lists | 203. Remove Linked List Elements |
733. Flood Fill | 206. Reverse Linked List |
83. Remove Duplicates from Sorted List | 116. Populating Next Right Pointers in Each Node |
145. Binary Tree Postorder Traversal | 94. Binary Tree Inorder Traversal |
101. Symmetric Tree | 77. Combinations |
46. Permutations | 226. Invert Binary Tree |
112. Path Sum | 1556A - A Variety of Operations |
136. Single Number | 169. Majority Element |