Реализация графов на java

//---------------------------------------------------------------------------
#include <iostream>
#include <stdio.h>
#include <stdlib.h>
#include <limits.h>
#include <string>
#include <string.h>
#include <set>
#include <cmath>
 
#pragma hdrstop
 
//---------------------------------------------------------------------------
 
#pragma argsused
using namespace std;
//---------------------------------------------------------------------------
typedef struct {            // type of structure describing the city
     char Name[11];         //name of  city
     int p;                 //number of neigbour cities
     int s_cost;            //city cost (defined as minimum sum of transportation costs to it + cost of the previous city) initially equal to infinity
     int **nr_cost;         //array for memorizing of neighbur city and the transportation cost to it
 } tcity;
//---------------------------------------------------------------------------
int  s=0,n=0,r=1;
//--------------------------------------------------------------------------- 
int mincostway(tcity* city, char Name1[11], char Name2[11]); 
//---------------------------------------------------------------------------
int main(int argc, char* argv[])
{
 printf("Input:\n");                                    //input the number of tests <= 10
 scanf("%d", &s);
 if((s>=0)&&(s<11))
  for(int i=0;i<s;i++)
  {  
 scanf("%d", &n);                                       // input the number of cities <= 10000
 if ((n>0)&&(n<10001))
  {
    tcity *city = new tcity[n];                         // reserve memory for array of structures (of city)
    for (int i=0;i<n;i++)
    {
     scanf("%s[a-z]",city[i].Name);                     //input the name of the city
     cin>>city[i].p;                                    //input the number of neighbour cities
     city[i].s_cost=pow(2,sizeof(int) * 8.0 - 1) - 1;   //give the city cost equal the infinity (this is maximum value for type int)
     city[i].nr_cost = new int *[city[i].p];            // reserve memory for array of neigbour cities
     for (int j=0;j<city[i].p;j++)                      //input the index and cost of neigbour cities
        {
         city[i].nr_cost[j]=new int [2];
         scanf("%d%d",&city[i].nr_cost[j][0],&city[i].nr_cost[j][1]);
         city[i].nr_cost[j][0]--;
        }
                 
    }
  
scanf("%d",&r);                             //input the number of paths to find <= 100
if((r>0)&&(r<101))
{ 
 char **s = new char* [r*2];
 for(int i=0;i<r*2;i++)                     //input NAME1 - source, NAME2 - destination
 {
    s[i] = new char [11];                   
    s[i+1] = new char [11];
    scanf("%s%s",s[i],s[i+1]);
    i++;
 }
 printf("\nOutput:\n");
 
 for(int i=0;i<r*2;i++)
 {
  printf("%d\n",mincostway(city,s[i],s[i+1]));          //output result
  i++;
 }
 
for (int count = 0; count < r*2; count++)
        delete [] s[count];
        
}
 
/*for(int i = 0; i<n;i++)
    for (int j=0;j<city[i].p;j++)
      delete[] city[i].nr_cost;*/
 delete[] city;
  }
  
  }
 return 0;
}
//---------------------------------------------------------------------------
//function returns minimal transportation cost between cities Name1 and Name2. 
//search of the way is performed with the help of Dejkstra algorithm
int mincostway(tcity* city,char Name1[11], char Name2[11])
{
 
int min_cost;                                       //length of the way between two neighbur cities with minimal cost 
int minindex_pos=-1;                                //index of theneighbur city with minimal transport cost
int minresult=pow(2,sizeof(int) * 8.0 - 1) - 1;     //minimal length of the way between two given cities
int count=0;                                        //counter of city visits
int first=-1,last=-1;                               //index of the first and the last city
set <int> SetCity;                                  //number of visited cities
 
//search for indexes of the first and the least cities
for (int i=0;i<n;i++)
     {
        if(!(strcmp(city[i].Name,Name1))) first=i;
        if(!(strcmp(city[i].Name,Name2))) last=i;
     }
if((last!=-1)&&(first!=-1))
    {
     city[first].s_cost=0;                              //cost of the first city is minimal and equal 0 
     while (count<n)                                    //search for length of the way until we walk though all cities
     {
        min_cost=pow(2,sizeof(int) * 8.0 - 1) - 1;      //length of the way with minimal cost is equal infinity
        for (int i=0;i<city[first].p;i++)               //go over the ways to neighbour cities 
        {
        if(!(SetCity.count(city[first].nr_cost[i][0])))//check if we have visited this city
        {
         //if not
         //check if city cost is bigger than sum of city cost of the previous city and its transportation cost
         //than the current city cost is equal the sum of city cost of the previous city and its transportation cost
         if (city[city[first].nr_cost[i][0]].s_cost>(city[first].s_cost)+city[first].nr_cost[i][1])
             city[city[first].nr_cost[i][0]].s_cost=city[first].nr_cost[i][1]+city[first].s_cost;
         //find index of city whis minimal cost
         if(min_cost>city[city[first].nr_cost[i][0]].s_cost)
            {
              min_cost=city[city[first].nr_cost[i][0]].s_cost;
              minindex_pos=city[first].nr_cost[i][0];
            }
          //check if we have reached the destination point  
          if (city[first].nr_cost[i][0]==last)
            if(minresult>city[city[first].nr_cost[i][0]].s_cost)
             {
                minresult=city[city[first].nr_cost[i][0]].s_cost;   //if its bigger than give it a new value
                //than we have to find other not visited cities
                first =0;
                while (SetCity.count(first)) first++;
             }
        }
        }
        //
        SetCity.insert(first);                          //mark current city as visited
        first=minindex_pos;                             //go to the city with minimal cost
        count++;                                        //increase counter of visited cities
     }
    }
    return minresult; 
}