743 B | 743 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, t, t_0 = mii()
for _ in range(n):
m, *l = mii()
cnt = 0
sm = 0
mx = 0
for i in range(m):
mx = max(mx, l[i])
if sm + l[i] - (mx - t_0 if mx >= t_0 else 0) <= t:
cnt += 1
sm += l[i]
else:
break
print(cnt)
if __name__ == "__main__":
tc = 1
for t in range(1, tc+1):
ret = solve()