a=[5,2,9,3,6,8] for i in range(len(a)-1): minIndex = i for j in range(i+1,len(a)): if a[minIndex]>a[i]: minIndex = j a[i],a[minIndex]=a[minIndex],a[i] print(a)
时间: 2024-03-24 22:40:08 浏览: 14
这段代码是使用选择排序对列表a进行排序。但是在选择最小值的时候,应该是 `if a[minIndex]>a[j]:` 而不是 `if a[minIndex]>a[i]:`,因为 `i` 是外层循环的迭代变量,而不是当前的最小值索引。正确的代码应该是:
```
a = [5, 2, 9, 3, 6, 8]
for i in range(len(a)-1):
minIndex = i
for j in range(i+1, len(a)):
if a[minIndex] > a[j]:
minIndex = j
a[i], a[minIndex] = a[minIndex], a[i]
print(a)
```
输出结果为:[2, 3, 5, 6, 8, 9],表示列表a已经按照从小到大的顺序排好了序。
相关问题
while len(own_pickup_node) > 0: route = [depot.depot_id] for i in range(min(len(own_pickup_node), 2)): minIndex = np.argmin([model.distance_matrix[depot.depot_id, own_pickup_node[j]] for j in range(0, len(own_pickup_node))]) minnode = own_pickup_node[minIndex] route.append(minnode) arrival = model.time_matrix[depot.depot_id, minnode] departure = arrival + service_time route.append(own_delivery_node[minIndex]) arrival = departure + model.time_matrix[minnode, own_delivery_node[minIndex]] departure += arrival + service_time last_node = own_delivery_node[minIndex] own_pickup_node.remove(minnode) own_delivery_node.remove(own_delivery_node[minIndex]) for j in own_pickup_node: next_minIndex = np.argmin([model.distance_matrix[last_node, j]]) next_minnode = own_pickup_node[next_minIndex] arrival = departure + model.time_matrix[last_node, next_minnode] if arrival <= model.demand_dict[next_minnode].end_time and arrival <= depot.dend_time: route.append(next_minnode) departure = arrival + service_time route.append(own_delivery_node[next_minIndex]) arrival = departure + model.time_matrix[next_minnode, own_delivery_node[next_minIndex]] departure += arrival + service_time last_node = own_delivery_node[next_minIndex] own_pickup_node.remove(next_minnode) own_delivery_node.remove(own_delivery_node[next_minIndex]) else: continue route.append(depot.depot_id) sol.route_list.append(route) vehicle_number = vehicle_number - 1 if vehicle_number == 0: break
这段代码实现了一个基于贪心算法的送货路径规划。具体来说,它会先将起点设为仓库,然后在所有尚未配对的取货点和配送点中,选取距离仓库最近的两个取货点进行配对,将它们的编号加入路径中。然后,它会根据这两个取货点所对应的配送点的时间窗口,计算出到达和离开的时间,并将这两个配送点的编号加入路径中。接着,它会在剩下的取货点和配送点中,选取距离上一个配送点最近的取货点进行配对,然后重复之前的操作,不断将取货点和配送点加入路径中,直到所有货物都配送完毕。
需要注意的是,这段代码中的距离矩阵、时间矩阵、时间窗口等信息都是由 model 对象提供的,而且这里采用了 NumPy 库中的 argmin 函数来查找距离最近的取货点。另外,这段代码中的 sol 对象则是一个 Solution 类的实例,它用于保存所有的路径方案。
def generateOwnCarRoute(service_time, model, sol): pickup_node = copy.deepcopy(model.demand_id_list[0: 16]) own_pickup_node = [] own_delivery_node = [] route = [] sol.route_list = [] depot = model.depot_dict['d1'] vehicle_number = depot.depot_capacity departure = 0 arrival = 0 for i in pickup_node: if i not in model.crowd_pickup_node: own_pickup_node.append(i) own_delivery_node.append(i+16) while vehicle_number > 0 and len(own_pickup_node) > 0: route.append(depot.depot_id) minIndex = np.argmin([model.distance_matrix[depot.depot_id, own_pickup_node[i]] for i in range(0, len(own_pickup_node))]) minnode = own_pickup_node[minIndex] route.append(minnode) arrival = model.time_matrix[depot.depot_id, minnode] departure = arrival + service_time route.append(own_delivery_node[minIndex]) arrival = departure + model.time_matrix[minnode, own_delivery_node[minIndex]] departure += arrival + service_time last_node = own_delivery_node[minIndex] own_pickup_node.remove(minnode) own_delivery_node.remove(own_delivery_node[minIndex]) for j in own_pickup_node: next_minIndex = np.argmin([model.distance_matrix[last_node, j]]) next_minnode = own_pickup_node[next_minIndex] arrival = departure + model.time_matrix[last_node, next_minnode] if arrival <= model.demand_dict[next_minnode].end_time and arrival <= depot.dend_time: route.append(next_minnode) departure = arrival + service_time route.append(own_delivery_node[next_minIndex]) arrival = departure + model.time_matrix[next_minnode, own_delivery_node[next_minIndex]] departure += arrival + service_time last_node = own_delivery_node[next_minIndex] own_pickup_node.remove(next_minnode) own_delivery_node.remove(own_delivery_node[next_minIndex]) else: continue route.append(depot.depot_id) sol.route_list.append(route) vehicle_number = vehicle_number - 1 route = [] print(sol.route_list) return sol.route_list 这段代码的问题是有可能vehicle_number为0了,但是owner_pickup_node的长度还不为0,这种情况怎么解决
这种情况下,程序会陷入无限循环,因为当所有车辆都被分配任务后,仍有剩余的pickup_node,但是vehicle_number为0,所以不会再有车辆来接这些节点。为了解决这个问题,可以在while循环条件中添加一个限制条件,即当所有车辆都被分配任务后,停止while循环。例如可以这样修改while循环的条件:
```
while vehicle_number > 0 and len(own_pickup_node) > 0 and len(sol.route_list) < model.depot_dict['d1'].depot_capacity:
```
这样,当所有车辆都被分配任务后,循环就会停止,避免了程序陷入无限循环的情况。