import sys
input = sys.stdin.readline

from collections import deque
def topsort(G):
    Q = deque()
    N = len(G)
    count = [0] * N
    for u in range(N):
        for v, _, _ in G[u]:
            count[v] += 1

    for u in range(N):
        if count[u] == 0:
            Q.append(u)
    anslst = []
    while Q:
        u = Q.pop()
        anslst.append(u)
        for v, _, _ in G[u]:
            count[v] -= 1
            if count[v] == 0:
                Q.append(v)
    return anslst


N, M = map(int, input().split())
G = [[] for i in range(N + 1)]
for i in range(M):
    u, v, l, a = map(int, input().split())
    G[u].append((v, l, a))

dp = [0] * (N + 1)
dp_sum = [0] * (N + 1)
dp[0] = 1
L = topsort(G)
if len(L) != N + 1:
    print("INF")
    exit()

mod = 10**9 + 7    
for u in L:
    for v, l, a in G[u]:
        dp[v] += dp[u] * a
        dp[v] %= mod
        dp_sum[v] += dp_sum[u] + dp[u] * l * a
        dp_sum[v] %= mod
        
print(dp_sum[-1])