主题
获取最小生成树 - GetMinimumSpanningTree
函数简介
在指定的图中计算最小生成树,连接图中所有节点且总权重最小。
接口名称
GetMinimumSpanningTreeDLL调用
c
long GetMinimumSpanningTree(long instance, long graphPtr);参数说明
| 参数名 | 类型 | 说明 |
|---|---|---|
| instance | 长整数型 | OLAPlug对象的指针,由 CreateCOLAPlugInterFace 接口生成。 |
| graphPtr | 长整数型 | 图的指针,由 CreateGraph 接口返回。 |
示例
SDK 调用
cpp
#include "OLAPlugServer.h"
OLAPlugServer ola;
long graphPtr = ola.CreateGraph("[{\"directed\":false,\"from\":\"上海\",\"to\":\"北京\",\"weight\":3.0},{\"directed\":false,\"from\":\"北京\",\"to\":\"深圳\",\"weight\":5.0}]");
if (graphPtr != 0) {
std::string mst = ola.GetMinimumSpanningTree(graphPtr);
ola.DeleteGraph(graphPtr);
}csharp
using OLAPlug;
var ola = new OLAPlugServer();
long graphPtr = ola.CreateGraph(@"[{"directed":false,"from":"上海","to":"北京","weight":3.0},{"directed":false,"from":"北京","to":"深圳","weight":5.0}]");
if (graphPtr != 0)
{
string mst = ola.GetMinimumSpanningTree(graphPtr);
ola.DeleteGraph(graphPtr);
}python
from OLAPlugServer import OLAPlugServer
ola = OLAPlugServer()
graph_ptr = ola.CreateGraph(r'[{"directed":false,"from":"上海","to":"北京","weight":3.0},{"directed":false,"from":"北京","to":"深圳","weight":5.0}]')
if graph_ptr != 0:
mst = ola.GetMinimumSpanningTree(graph_ptr)
ola.DeleteGraph(graph_ptr)java
import com.olaplug.OLAPlugServer;
OLAPlugServer ola = new OLAPlugServer();
long graphPtr = ola.CreateGraph("[{\"directed\":false,\"from\":\"上海\",\"to\":\"北京\",\"weight\":3.0},{\"directed\":false,\"from\":\"北京\",\"to\":\"深圳\",\"weight\":5.0}]");
if (graphPtr != 0) {
ola.GetMinimumSpanningTree(graphPtr);
ola.DeleteGraph(graphPtr);
}cpp
var ola = com("OlaPlug.OlaSoft")
var graphPtr = ola.CreateGraph("[{\"directed\":false,\"from\":\"上海\",\"to\":\"北京\",\"weight\":3.0},{\"directed\":false,\"from\":\"北京\",\"to\":\"深圳\",\"weight\":5.0}]")
if(graphPtr) {
ola.GetMinimumSpanningTree(graphPtr);
ola.DeleteGraph(graphPtr)
}vbscript
Set ola = CreateObject("OlaPlug.OlaSoft")
graphPtr = ola.CreateGraph("[{\"directed\":false,\"from\":\"上海\",\"to\":\"北京\",\"weight\":3.0},{\"directed\":false,\"from\":\"北京\",\"to\":\"深圳\",\"weight\":5.0}]")
If graphPtr <> 0 Then
ola.GetMinimumSpanningTree(graphPtr);
ola.DeleteGraph(graphPtr)
End Iftext
.局部变量 ola, OLAPlug
ola.创建 ()
graphPtr = ola.CreateGraph (“[{\“directed\“:false,\“from\“:\“上海\“,\“to\“:\“北京\“,\“weight\“:3.0},{\“directed\“:false,\“from\“:\“北京\“,\“to\“:\“深圳\“,\“weight\“:5.0}]“)
.如果真 (graphPtr ≠ 0)
ola.GetMinimumSpanningTree(graphPtr);
ola.DeleteGraph (graphPtr)
.如果真结束aardio
import OLAPlugServer;
var ola = OLAPlugServer();
var graphPtr = ola.CreateGraph("[{\"directed\":false,\"from\":\"上海\",\"to\":\"北京\",\"weight\":3.0},{\"directed\":false,\"from\":\"北京\",\"to\":\"深圳\",\"weight\":5.0}]");
if(graphPtr){
ola.GetMinimumSpanningTree(graphPtr);
ola.DeleteGraph(graphPtr);
}text
变量 ola <类型 = OLAPlugServer>
ola = 新建 OLAPlugServer
长整数 graphPtr = ola.CreateGraph("[{\"directed\":false,\"from\":\"上海\",\"to\":\"北京\",\"weight\":3.0},{\"directed\":false,\"from\":\"北京\",\"to\":\"深圳\",\"weight\":5.0}]")
如果真 (graphPtr ≠ 0)
{
ola.GetMinimumSpanningTree(graphPtr);
ola.DeleteGraph(graphPtr)
}cpp
#include "OLAPlugServer.h"
OLAPlugServer ola;
long graphPtr = ola.CreateGraph("[{\"directed\":false,\"from\":\"上海\",\"to\":\"北京\",\"weight\":3.0},{\"directed\":false,\"from\":\"北京\",\"to\":\"深圳\",\"weight\":5.0}]");
if (graphPtr != 0) {
ola.GetMinimumSpanningTree(graphPtr);
ola.DeleteGraph(graphPtr);
}原生 DLL 调用
cpp
long instance = CreateCOLAPlugInterFace();
long graphPtr = CreateGraph(instance, "[{\"directed\":false,\"from\":\"上海\",\"to\":\"北京\",\"weight\":3.0},{\"directed\":false,\"from\":\"北京\",\"to\":\"深圳\",\"weight\":5.0}]");
if (graphPtr != 0) {
std::string mst = ola.GetMinimumSpanningTree(graphPtr);
DeleteGraph(instance, graphPtr);
}csharp
using System.Runtime.InteropServices;
[DllImport("OLAPlug_x64.dll", CallingConvention = CallingConvention.StdCall)]
static extern long CreateCOLAPlugInterFace();
long instance = CreateCOLAPlugInterFace();
long graphPtr = CreateGraph(instance, @"[{"directed":false,"from":"上海","to":"北京","weight":3.0},{"directed":false,"from":"北京","to":"深圳","weight":5.0}]");
if (graphPtr != 0) {
string mst = ola.GetMinimumSpanningTree(graphPtr);
DeleteGraph(instance, graphPtr);
}python
from ctypes import CDLL, c_int, c_int64
ola = CDLL("OLAPlug_x64.dll")
ola.CreateCOLAPlugInterFace.restype = c_int64
instance = ola.CreateCOLAPlugInterFace()
graph_ptr = ola.CreateGraph(instance, b'[{"directed":false,"from":"上海","to":"北京","weight":3.0},{"directed":false,"from":"北京","to":"深圳","weight":5.0}]')
if graph_ptr:
mst = ola.GetMinimumSpanningTree(graph_ptr)
ola.DeleteGraph(instance, graph_ptr)返回值
| 返回值 | 说明 |
|---|---|
| (返回值) | 返回最小生成树信息的字符串指针,格式为JSON:。 |
json
{
"totalWeight": 9.0,
"edges": [
{"from": "A", "to": "C", "weight": 2.0},
{"from": "B", "to": "C", "weight": 1.0},
{"from": "D", "to": "E", "weight": 2.0},
{"from": "A", "to": "B", "weight": 4.0}
]
}| 字段名 | 类型 | 说明 |
|---|---|---|
| totalWeight | 浮点数 | totalWeight 字段值。 |
| edges | 数组 | edges 结果列表,详见下方字段说明。 |
如果无法生成最小生成树返回0。
返回的字符串指针需要调用 FreeStringPtr 释放内存。
edges 元素字段说明:
| 字段名 | 类型 | 说明 |
|---|---|---|
| from | 字符串 | from 字段。 |
| to | 字符串 | to 字段。 |
| weight | 浮点数 | weight 字段。 |
注意事项
| 项目 | 说明 |
|---|---|
| 最小生成树要求图是连通的 | 最小生成树要求图是连通的,如果图不连通返回0。 |
| 最小生成树包含 n-1 条边(n为节点数) | 最小生成树包含 n-1 条边(n为节点数)。 |
