626 B | 626 chars
import sys
from math import sqrt, pi, sin, factorial, ceil, floor
from datetime import datetime, timedelta
BLANK = " "
# inp = input
inp = lambda : sys.stdin.readline()[:-1].strip()
mii = lambda x = BLANK : [*map(int,inp().split(x))]
mfi = lambda x = BLANK : [*map(float,inp().split(x))]
ii = lambda : int(inp())
fi = lambda : float(inp())
p = print
def solve():
N, M = mii()
l = [mii() for _ in range(M)]
room = [0] * (N + 1)
for r, s, e in l:
if room[r] <= s:
p("YES")
room[r] = e
else:
p("NO")
if __name__ == "__main__":
tc = 1
for t in range(1, tc+1):
ret = solve()