import sys
input = sys.stdin.buffer.readline
sys.setrecursionlimit(10 ** 7)
mod = 10**9+7

N, M = map(int, input().split())
deg = [0] * (N+1)
go = [[] for _ in range(N+1)]
back = [[] for _ in range(N+1)]
for _ in range(M):
    a, b, c, d = map(int, input().split())
    go[a].append((b, c, d))
    back[b].append((a, c, d))
    deg[b] += 1

topo = []
q = []
for i, d in enumerate(deg):
    if d == 0:
        q.append(i)
while q:
    s = q.pop()
    topo.append(s)
    for t, _, _ in go[s]:
        deg[t] -= 1
        if deg[t] == 0:
            q.append(t)

if len(topo) < N + 1:
    print("INF")
    exit()


cnt = [0] * (N + 1)
cnt[N] = 1
for s in topo[::-1]:
    for t, _, num in back[s]:
        cnt[t] += num * cnt[s]
        cnt[t] %= mod

ans = 0
for s in topo:
    for t, d, num in go[s]:
        ans += d * num * cnt[t]
        ans %= mod
print(ans)