1.0 KB | 1042 chars
"""
[25842: Tetrooj Box](https://www.acmicpc.net/problem/25842)
Tier: Silver 5
Category: implementation, simulation
"""
import sys
from math import sqrt, pi, sin, factorial, ceil, floor
from datetime import datetime, timedelta
SYS_INPUT = True
RECURSION_LIMIT = 10 ** 7
SET_RECURSION = False
BLANK = " "
if SET_RECURSION:
sys.setrecursionlimit(RECURSION_LIMIT)
inp = lambda : sys.stdin.readline().rstrip() if SYS_INPUT else input()
mii = lambda : [*map(int,inp().split())]
mfi = lambda : [*map(float,inp().split())]
ii = lambda : int(inp())
fi = lambda : float(inp())
isplit = lambda : inp().split()
p = print
def gcd(a, b): return gcd(b, a % b) if b > 0 else a
def lcm(a, b): return a * b // gcd(a, b)
def solve():
n, m = mii()
l = [0 for _ in range(n + 1)]
for _ in range(m):
w, h, x = mii()
mx = 0
for i in range(x, x + w):
mx = max(mx, l[i])
for i in range(x, x + w):
l[i] = mx + h
print(max(l))
if __name__ == "__main__":
tc = 1
for t in range(1, tc+1):
ret = solve()