a = int(input())
b = input()
b = b.split(' ')
g = 0
for n in b:
    e = int(n[3])-int(n[2])-int(n[1])-int(n[0])
    if e > 0:
        g += 1
print(g)

求助各位大佬，哪里出问题了？为什么#4会RE啊（哭）自己也试不出来RE的情况