Thread: need some help with ford bellman algorithm

Hi guys, friend of mine gived me code that works correctly but i had to do for my homevork an application that shows full fastest road and distance. Code he gived to me shows only distance and I can't figure out how to edit it so it will show path also.
Thnx for your suggestions

Code:

#include <stdio.h>
#include <conio.h>
#include <stdlib.h>
#include <string.h>
#define nieskonczonosc 100000   //infinity
 
#define MIN(a,b) (a<b)?a:b
 
void main(void)
{
FILE *plik;
int     n; //number of verticles
int     A[100][100];
int     D[100];
char    s[5];
int     i,j,k;
int N;
 
 
if ((plik=fopen("graf.txt","r"))==NULL)
printf("missing file graf.txt!\n"); else
{
fscanf(plik,"%i",&n);
printf("number of verticles: %i\n",n);
for (j=0;j<n;j++)
for (i=0;i<n;i++)
{
fscanf(plik,"%s",s);
if (strcmp(s,"*")!=0)
A[j][i]=atoi(s); else A[j][i]=nieskonczonosc;
}
fclose(plik);
 
for (i=0;i<n;i++) D[i]=A[0][i];
 
//start
for (k=1;k<=n-2;k++)
{
for (i=1;i<n;i++)
for (j=0;j<n;j++)
{
if (D[j]+A[j][i]>nieskonczonosc)
N=nieskonczonosc; 
else{


N=D[j]+A[j][i];
D[i]=MIN(D[i],N);
}
}
}


for (i=0;i<n;i++)
if (D[i]<nieskonczonosc)
printf("distance to (%i) = %i\n",i+1,D[i]);
else
printf("distance to (%i) = %s\n",i+1,"*");
}
}

.txt file named graf.txt

9
0 5 * 23 * 7 * * *
5 0 8 * * * 23 * *
* 8 0 4 7 9 * * *
23 * 4 0 23 * * * *
* * 7 23 0 2 * * 4
7 * 9 * 2 0 2 * *
* 23 * * * 2 0 1 *
* * * * * * 1 0 2
* * * * 4 * * 2 0


and another sample of graf.txt

6
0 * 3 * * *
* 0 2 1 3 *
3 2 0 * 1 *
* 1 * 0 * *
* 3 1 * 0 6
* * * * 6 0

Your friend is doing you no favors giving you answers to homework. This prevents you from learning the material yourself, meaning you will not be able to handle future assignments either.

Study and practice the concepts yourself, so you are properly equipped to do your own work.

I will not comment on the code you posted, except for two general points:

• FAQ > main() / void main() / int main() / int main(void) / int main(int argc, char *argv[]) - Cprogramming.com
• https://en.wikipedia.org/wiki/Indent_style

Originally Posted by Radek

Hi guys, friend of mine gived me code that works correctly but i had to do for my homevork an application that shows full fastest road and distance. Code he gived to me shows only distance and I can't figure out how to edit it so it will show path also.

That's a very uninspiring speech.
I'd be surprised if this wasn't cross-posted.