927 B | 917 chars
import sys
from math import sqrt, pi, sin, factorial, ceil, floor
from datetime import datetime, timedelta
# sys.setrecursionlimit(10**7)
BLANK = " "
# inp = input
inp = lambda : sys.stdin.readline().rstrip()
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 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() # N: 고양이, M: 과자
l = [mii() for _ in range(m)]
total = 1
for i in l:
total = lcm(total, i[0])
cnt = [0] * n
for i in l:
mul = total // i[0]
for j in range(n):
cnt[j] += i[j + 1] * mul
A = max(cnt) - min(cnt)
B = total
A, B = A // gcd(A, B), B // gcd(A, B)
if A % B == 0:
p(A // B)
else:
p(f"{A}/{B}")
if __name__ == "__main__":
tc = ii()
for t in range(1, tc+1):
ret = solve()