Problem p03450 (python)

Fixed submission:
import sys
sys.setrecursionlimit(200002)

def try_dfs_fill_distance(graph, cur_node, cur_dist_from_origin, distance_cache):
    found_conflicts = False
    for neighbor_node_data in graph[cur_node]:
        neighbor_node, neighbor_distance_from_cur = neighbor_node_data
        neighbor_dist_from_origin = (cur_dist_from_origin + neighbor_distance_from_cur)
        #print("cur_node:{} neighbor_node:{} neighbor_dist:{} origin to {}:{}".format(cur_node, neighbor_node, neighbor_distance_from_cur, neighbor_node, neighbor_dist_from_origin))
        if distance_cache[neighbor_node] == None:
            distance_cache[neighbor_node] = neighbor_dist_from_origin
            found_conflicts = try_dfs_fill_distance(graph, neighbor_node, neighbor_dist_from_origin, distance_cache)
        else:
            if distance_cache[neighbor_node] != neighbor_dist_from_origin:
                #print("{} {} {}".format((distance_cache[neighbor_node] == None), distance_cache[neighbor_node], neighbor_dist_from_origin))
                found_conflicts = True

        if found_conflicts:
            break

    return found_conflicts

if __name__ == '__main__':
    n, m = list(map(int, input().split(" ")))
    graph = [[] for _ in range(n + 1)]
    for _ in range(m):
        l, r, d = list(map(int, input().split()))
        graph[l].append((r, d))
        graph[r].append((l, -d))

    distance_cache = [None for _ in range(n + 1)]
    has_conflict = False
    for i in range(1, len(distance_cache)):
        if distance_cache[i] == None:
            distance_cache[i] = 0
            has_conflict = try_dfs_fill_distance(graph, i, 0, distance_cache)
            if has_conflict:
                break

    print("No" if has_conflict else "Yes")

Buggy submission (verdict: Runtime Error):
def try_dfs_fill_distance(graph, cur_node, cur_dist_from_origin, distance_cache):
    found_conflicts = False
    for neighbor_node_data in graph[cur_node]:
        neighbor_node, neighbor_distance_from_cur = neighbor_node_data
        neighbor_dist_from_origin = (cur_dist_from_origin + neighbor_distance_from_cur)
        #print("cur_node:{} neighbor_node:{} neighbor_dist:{} origin to {}:{}".format(cur_node, neighbor_node, neighbor_distance_from_cur, neighbor_node, neighbor_dist_from_origin))
        if distance_cache[neighbor_node] == None:
            distance_cache[neighbor_node] = neighbor_dist_from_origin
            found_conflicts = try_dfs_fill_distance(graph, neighbor_node, neighbor_dist_from_origin, distance_cache)
        else:
            if distance_cache[neighbor_node] != neighbor_dist_from_origin:
                #print("{} {} {}".format((distance_cache[neighbor_node] == None), distance_cache[neighbor_node], neighbor_dist_from_origin))
                found_conflicts = True

        if found_conflicts:
            break

    return found_conflicts

if __name__ == '__main__':
    n, m = list(map(int, input().split(" ")))
    graph = [[] for _ in range(n + 1)]
    for _ in range(m):
        l, r, d = list(map(int, input().split()))
        graph[l].append((r, d))
        graph[r].append((l, -d))

    distance_cache = [None for _ in range(n + 1)]
    has_conflict = False
    for i in range(1, len(distance_cache)):
        if distance_cache[i] == None:
            distance_cache[i] = 0
            has_conflict = try_dfs_fill_distance(graph, i, 0, distance_cache)
            if has_conflict:
                break

    print("No" if has_conflict else "Yes")

Buggy submission (verdict: Runtime Error):
def try_dfs_fill_distance(graph, cur_node, cur_dist_from_origin, distance_cache):
    found_conflicts = False
    for neighbor_node_data in graph[cur_node]:
        neighbor_node, neighbor_distance_from_cur = neighbor_node_data
        neighbot_dist_from_origin = (cur_dist_from_origin + neighbor_distance_from_cur)
        if distance_cache[neighbor_node] == None:
            distance_cache[neighbor_node] = neighbot_dist_from_origin
            try_dfs_fill_distance(graph, neighbor_node, neighbot_dist_from_origin, distance_cache)
        else:
            if distance_cache[neighbor_node] != neighbot_dist_from_origin:
                found_conflicts = True
                break

    return found_conflicts

if __name__ == '__main__':
    n, m = list(map(int, input().split(" ")))
    graph = [[] for _ in range(n + 1)]
    for _ in range(m):
        l, r, d = list(map(int, input().split()))
        graph[l].append((r, d))
        graph[r].append((l, -d))

    distance_cache = [None for _ in range(n + 1)]
    has_conflict = False
    for i in range(1, len(distance_cache)):
        if distance_cache[i] == None:
            distance_cache[i] = 0
            has_conflict = try_dfs_fill_distance(graph, i, 0, distance_cache)
            if not has_conflict:
                break

    print("No" if has_conflict else "Yes")