*和&的转化出现了问题？请看代码的注释行，改动前的代码是可以运行的。

#include "stdio.h"    
#include "stdlib.h"   
#include "io.h"  
#include "math.h"  
#include "time.h"

#define OK 1
#define ERROR 0
#define TRUE 1
#define FALSE 0
#define MAXVEX 100 

typedef int Status; 
typedef char VertexType; 
typedef int EdgeType; 

typedef struct EdgeNode 
{
    int adjvex;   
    EdgeType info;      
    struct EdgeNode *next; 
}EdgeNode;

typedef struct VertexNode
{
    VertexType data; 
    EdgeNode *firstedge;
}VertexNode, AdjList[MAXVEX];

typedef struct
{
    AdjList adjList; 
    int numNodes,numEdges; 
}GraphAdjList;


void  CreateALGraph(GraphAdjList &G)/*此处将*G改为&G*/
{
    int i,j,k;
    EdgeNode *e;
    printf("输入顶点数和边数:\n");
    scanf("%d,%d",&G.numNodes,&G.numEdges); /* 此处将两个&G->改为&G. */
    for(i = 0;i < G.numNodes;i++) /* 此处将G->改为G. */
    {
        scanf(&G.adjList[i].data);  /* 此处将两个&G->改为&G. */
        G.adjList[i].firstedge=NULL;    /*此处将G->改为G. */
    }


    for(k = 0;k < G.numEdges;k++)/* 此处将G->改为G. */
    {
        printf("输入边(vi,vj)上的顶点序号:\n");
        scanf("%d,%d",&i,&j); 
        e=(EdgeNode *)malloc(sizeof(EdgeNode));
        e->adjvex=j;                                    
        e->next=G.adjList[i].firstedge; /* 此处将G->改为G. */
        G.adjList[i].firstedge=e;       /* 此处将G->改为G. */               

        e=(EdgeNode *)malloc(sizeof(EdgeNode));
        e->adjvex=i;                                       
        e->next=G.adjList[j].firstedge; /* 此处将G->改为G. */
        G.adjList[j].firstedge=e;       /*此处将G->改为G. */               
    }
}

int main(void)
{    
    GraphAdjList G;    
    CreateALGraph(G);/*将&删去*/

    return 0;
}

c语言不支持引用，你将源代码后缀修改为cpp

#include "stdio.h"    
#include "stdlib.h"   
#include <sys/io.h>
#include "math.h"  
#include "time.h"

#define OK 1
#define ERROR 0
#define TRUE 1
#define FALSE 0
#define MAXVEX 100 

typedef int Status; 
typedef char VertexType; 
typedef int EdgeType; 

typedef struct EdgeNode 
{
    int adjvex;   
    EdgeType info;      
    struct EdgeNode *next; 
}EdgeNode;

typedef struct VertexNode
{
    VertexType data; 
    EdgeNode *firstedge;
}VertexNode, AdjList[MAXVEX];

typedef struct
{
    AdjList adjList; 
    int numNodes,numEdges; 
}GraphAdjList;


void  CreateALGraph(GraphAdjList &G)/*此处将*G改为&G*/
{
    int i,j,k;
    EdgeNode *e;
    printf("输入顶点数和边数:\n");
    scanf("%d,%d",&G.numNodes,&G.numEdges); /* 此处将两个&G->改为&G. */
    for(i = 0;i < G.numNodes;i++) /* 此处将G->改为G. */
    {
        scanf(&G.adjList[i].data);  /* 此处将两个&G->改为&G. */
        G.adjList[i].firstedge=NULL;    /*此处将G->改为G. */
    }


    for(k = 0;k < G.numEdges;k++)/* 此处将G->改为G. */
    {
        printf("输入边(vi,vj)上的顶点序号:\n");
        scanf("%d,%d",&i,&j); 
        e=(EdgeNode *)malloc(sizeof(EdgeNode));
        e->adjvex=j;                                    
        e->next=G.adjList[i].firstedge; /* 此处将G->改为G. */
        G.adjList[i].firstedge=e;       /* 此处将G->改为G. */               

        e=(EdgeNode *)malloc(sizeof(EdgeNode));
        e->adjvex=i;                                       
        e->next=G.adjList[j].firstedge; /* 此处将G->改为G. */
        G.adjList[j].firstedge=e;       /*此处将G->改为G. */               
    }
}

int main(void)
{    
    GraphAdjList G;    
    CreateALGraph(G);/*将&删去*/

    return 0;
}

我这里通过编译。