import sys


s = []
vis = [0] * 100
for line in sys.stdin:  #读取数据
    a = line.split(" ")
    s.append((int(a[0]), int(a[1]), int(a[2])))
n = len(s)
ans = 0
cnt = 0
s.sort(key=lambda x: (x[1], x[0]))
for i in range(n):
    __________
    for j in range(s[i][0] - 1, s[i][1]):
        if vis[j] == 1:
            cnt += 1
    if cnt < s[i][2]:
        for k in range(__________):
            __________
            if vis[k] == 0:
                vis[k] = 1
                cnt += 1
            if cnt == s[i][2]:
                break
print(ans)