DIJKSRTRA's ALGORITHM C

dijkstra.c

#include<stdio.h>
#include<stdlib.h>
#include<iostream>
#include<string.h>
#include<math.h>
#include<time.h>
#include<string.h>
using namespace std;

#define IN 999


int *intrev (int *orig,unsigned short int b)
{
    unsigned short int a=0;
    int swap;
     
    for(a;a<--b;a++) //increment a and decrement b until they meet eachother
    {
        swap=orig[a];       //put what's in a into swap space
        orig[a]=orig[b];    //put what's in b into a
        orig[b]=swap;       //put what's in the swap (a) into b
    }
     
    return orig;    //return the new (reversed) string (a pointer to it)
}
  
int dijsktra(int n , int **cost,int source,int target)
{
    int dist[n],prev[n],i,m,min,start,d,j;
    int selected[n];
    for ( i = 0 ; i < n ; i++)
    	selected[i] = 0 ; 
    
    int path[n];
    for(i=1;i< n;i++)
    {
        dist[i] = IN;
        prev[i] = -1;
    }
    start = source;
    selected[start]=1;
    dist[start] = 0;
    while(selected[target] ==0)
    {
        min = IN;
        m = 0;
        for(i=1;i< n;i++)
        {
            d = dist[start] +cost[start][i];
            if(d< dist[i]&&selected[i]==0)
            {
                dist[i] = d;
                prev[i] = start;
            }
            if(min>dist[i] && selected[i]==0)
            {
                min = dist[i];
                m = i;
            }
        }
        start = m;
        selected[start] = 1;
    }
    start = target;
    j = 0;
    while(start != -1)
    {
        path[j++] = start ;// + 65;
	//cout << path[j] << endl;
        start = prev[start];
    }
    //path[j]='\0';
     
    intrev(path, j);
    
    for ( i = 0 ; i < j ; i++ )
    	cout << path[i] << "  "  ;
    cout << endl;
    return dist[target];
}
main()
{
    int i,j,w,ch,co;
    int **cost , n;
    int source, target,x,y;
    
    printf("Enter the No of nodes: ");
    cin >> n;
    
    cost = (int**) malloc(n*sizeof(int*));
    for (int i = 0; i < n; i++)
       cost[i] = (int*) malloc(n*sizeof(int));
    
    for(i=1;i< n;i++)
    for(j=1;j< n;j++)
    	cost[i][j] = IN;
	
    srand(time(NULL));
    for(x=1;x< n;x++)
    {
        for(y=x+1;y< n;y++)
        {
            w = rand() %10 ;  // random weights. you can change as per your need.
	    cout << "Cost : " << x << " -> " << y << " = "  << w << endl;
            cost [x][y] = cost[y][x] = w;
        }
    }
    
    printf("\nEnter The Source:");
    cin >> source;
    printf("\nEnter The Target");
    cin >> target ;
    printf("\nShortest Path Algorithm(DIJKSRTRA's ALGORITHM)\n");
    co = dijsktra(n, cost,source,target);
    printf("\nShortest Path Cost: %d ",co);
    cout << endl;
}