最短路径(Floyd-Warshall实现)

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>

#define MaxVertexNodeNumSize 1000
#define MaxVertexNodeNameSize 100
#define INFINITY 10000

struct VertexBodyNode
{
    char VertexName[MaxVertexNodeNameSize];
    int ArcWeight;
    int VertexIndex;
    struct VertexBodyNode *Next;
};

struct VertexHeadNode
{
    char VertexName[MaxVertexNodeNameSize];
    int VertexWeight;
    struct VertexBodyNode *Next;
};

struct _Graph
{
    struct VertexHeadNode VertexHeadNodeList[MaxVertexNodeNumSize];
    int ArcNum,VertexNum;
};

int VertexName2Index(struct _Graph *DirectedGraph,char *VName)
{
    int i;
    for(i = 0; i < DirectedGraph -> VertexNum; i ++)
    {
        if(strcmp(DirectedGraph -> VertexHeadNodeList[i].VertexName,VName)==0)
        {
            return i;
        }
    }
    return -1;
}

void AddOneArc(struct _Graph *DirectedGraph,int ArcIndex_1,int ArcIndex_2,int AWeight)
{
    struct VertexBodyNode *BNode = malloc(sizeof(struct VertexBodyNode));

    strcpy(BNode -> VertexName,DirectedGraph -> VertexHeadNodeList[ArcIndex_2].VertexName);

    BNode -> ArcWeight = AWeight;
    BNode -> VertexIndex = ArcIndex_2;
    BNode -> Next = NULL;

    struct VertexBodyNode *TmpPointer;
    TmpPointer = DirectedGraph -> VertexHeadNodeList[ArcIndex_1].Next;
    while(TmpPointer != NULL && TmpPointer -> Next != NULL)
    {
        TmpPointer = TmpPointer -> Next;
    }
    if(TmpPointer==NULL)
    {
        DirectedGraph -> VertexHeadNodeList[ArcIndex_1].Next = BNode;
    }
    else
    {
        TmpPointer -> Next = BNode;
    }
}

struct _Graph *UGCreat(int ArcSum,int VertexSum)
{
    int i,j;
    struct _Graph *DirectedGraph = malloc(sizeof(struct _Graph));
    DirectedGraph -> ArcNum = ArcSum;
    DirectedGraph -> VertexNum = VertexSum;

    for(i = 0; i < VertexSum; i ++)
    {
        scanf("%s %d",DirectedGraph -> VertexHeadNodeList[i].VertexName,&DirectedGraph -> VertexHeadNodeList[i].VertexWeight);
    }

    for(i = 0; i < VertexSum; i ++)
    {
        DirectedGraph -> VertexHeadNodeList[i].Next = NULL;
    }

    for(i = 0; i < ArcSum; i ++)
    {
        char Arc_1[MaxVertexNodeNameSize];
        char Arc_2[MaxVertexNodeNameSize];
        int ArcIndex_1;
        int ArcIndex_2;
        int ArcWeight;

        scanf("%s %s %d",Arc_1,Arc_2,&ArcWeight);

        ArcIndex_1 = VertexName2Index(DirectedGraph,Arc_1);
        ArcIndex_2 = VertexName2Index(DirectedGraph,Arc_2);

        AddOneArc(DirectedGraph,ArcIndex_1,ArcIndex_2,ArcWeight);
    }
    return DirectedGraph;
}

void Travel(struct _Graph *DirectedGraph)
{
    char StartingPoint[MaxVertexNodeNameSize];
    char OverPoint[MaxVertexNodeNameSize];

    printf("Input start and over
");
    scanf("%s %s",StartingPoint,OverPoint);

    int StartIndex = VertexName2Index(DirectedGraph,StartingPoint);
    int OverIndex = VertexName2Index(DirectedGraph,OverPoint);

    struct VertexBodyNode *TmpPointer;
    TmpPointer = DirectedGraph -> VertexHeadNodeList[StartIndex].Next;
    while(TmpPointer != NULL)
    {
        if(OverIndex==TmpPointer -> VertexIndex)
        {
            printf("Distance:%d GetVertexPointSum:%d",TmpPointer->ArcWeight
                   ,DirectedGraph -> VertexHeadNodeList[StartIndex].VertexWeight+DirectedGraph -> VertexHeadNodeList[OverIndex].VertexWeight);
            break;
        }
        else
        {
            TmpPointer = TmpPointer -> Next;
        }
    }
}

void FloydShortestPath(struct _Graph *DirectedGraph,char *Origin,char *Destination)
{
    int OIndex = VertexName2Index(DirectedGraph,Origin);
    int DIndex = VertexName2Index(DirectedGraph,Destination);
    
    int i,j,k;
    struct VertexBodyNode *TmpPointer;
    int A[DirectedGraph->VertexNum][DirectedGraph->VertexNum];
    int Path[DirectedGraph->VertexNum][DirectedGraph->VertexNum];
    for(i = 0;i < DirectedGraph->VertexNum;i ++)
    {
        for(j = 0;j < DirectedGraph->VertexNum;j ++)
        {
            A[i][j] = INFINITY;
            if(i == j)
            {
                A[i][j] = 0;
            }
            Path[i][j] = j;
        }
    }
    for(i = 0;i < DirectedGraph->VertexNum;i ++)
    {
        TmpPointer = DirectedGraph -> VertexHeadNodeList[i].Next;
        while(TmpPointer != NULL)
        {
            A[i][TmpPointer->VertexIndex] = TmpPointer -> ArcWeight;
            TmpPointer = TmpPointer -> Next;
        }
    }
    
    for(i = 0;i < DirectedGraph->VertexNum;i ++)
    {
        for(j = 0;j < DirectedGraph->VertexNum;j ++)
        {
            for(k = 0;k < DirectedGraph->VertexNum;k ++)
            {
                if(A[j][k]>A[j][i]+A[i][k])
                {
                    A[j][k] = A[j][i]+A[i][k];
                    Path[j][k] = Path[j][i];
                }
            }
        } 
    } 
    
    int TmpIndex = Path[OIndex][DIndex];
    printf("%s -> ",DirectedGraph->VertexHeadNodeList[OIndex].VertexName);
    while(TmpIndex != DIndex)
    {
        printf("%s -> ",DirectedGraph->VertexHeadNodeList[TmpIndex].VertexName);
        TmpIndex = Path[TmpIndex][DIndex];
    }
    printf("%s    Distance:%d",DirectedGraph->VertexHeadNodeList[DIndex].VertexName,A[OIndex][DIndex]);
}

int main()
{
    struct _Graph *G = UGCreat(8,5);

//    Travel(G);
    char Origin[MaxVertexNodeNameSize];
    char Destination[MaxVertexNodeNameSize];
    printf("Input Origin && Destination:
");
    scanf("%s %s",Origin,Destination);
    FloydShortestPath(G,Origin,Destination);
    return 0;
}

/*
        beijing 18
        zhengzhou 10
        hefei 9
        nanjing 12
        guangzhou 14
        beijing zhengzhou 7
        beijing hefei 9
        beijing nanjing 8
        zhengzhou hefei 5
        hefei nanjing 3
        zhengzhou guangzhou 7
        hefei guangzhou 8
        nanjing guangzhou 6
*/