Bellman-Ford最短路

def solve(____):
    n = int(____)
    start = int(____)
    end = int(____)
    edges_list = []
    for e in edges.split(____):
        u, v, w = map(int, e.split(____))
        edges_list.append((____))
    dist = [float(____)] * n
    dist[start] = ____
    for _ in range(____):
        for u, v, w in edges_list:
            if dist[u] != float(____) and dist[v] > dist[u] + w:
                dist[v] = dist[u] + w
    print(dist[end] if dist[end] != float(____) else -____)