from collections import defaultdict
import sys
input = sys.stdin.buffer.readline
sys.setrecursionlimit(10 ** 7)

N = int(input())
card = defaultdict(int)
for _ in range(N):
    K, L, D = map(int, input().split())
    two = pow(2, D)
    for _ in range(K):
        card[L] ^= 1
        L += two

ans = -1
for k, v in card.items():
    if v:
        ans = k
print(ans)