CN LAB PROGRAM DISTANCE VECTOR ALGORITHM

#include<stdio.h>

#include<stdlib.h>

#define NUL 1000

#define NODES 10

struct node

{

int t[NODES][3];

};

struct node n[NODES];

typedef struct node NOD;

int main()

{

void init(int,int);

void inp(int,int);

void caller(int,int);

void op(int,int,int);

void find(int,int);

int i,j,x,y,no;

do

{

printf("\n enter the no of nodes required(less than 10):");

scanf("%d",&no);

}while(no>10||no<0);  

for(i=0;i<no;i++)

{

init(no,i);

inp(no,i);

}

printf("\n the configuration of the nodes after initialization is as follows”);                              for(i=0;i<no;i++)

op(no,i,0);

for(j=0;j<no;j++)

{

for(i=0;i<no;i++)

caller(no,i);

}printf("\n the configuration of the nodes after the comparision of the paths is as follows:");

for(i=0;i<no;i++)

op(no,i,1);

while(1) {

printf("\n enter 0 to exit or any key to find the shortest path:");

scanf("%d",&j);

if(!j) break;

system("clear");

do{

printf("enter the nodes between which path is to befound:")

scanf("%d%d",&x,&y);

}

while((x<0||x>no)&&(y<0||y>no));

printf("\n the most suitable result from node %d to %d is as follows\n",x,y);

find(x,y);

printf("%d",y);

printf("the length of the shortest path between node %d & %d is%d",x,y,n[x-1].t[y-1][2]);

}

}

void init(int no,int x)

{

int i;

for(i=0;i<no;i++)

{

n[x].t[i][1]=i;

n[x].t[i][2]=999;

n[x].t[i][3]=NUL;

}

n[x].t[x][2]=0;

n[x].t[x][3]=x;

}

void inp(int no,int x)

{

int i;

printf("\n enter the dist from nodes %d to other node",x+1);

printf("\n enter 999 if there is no direct\n");

for(i=0;i<no;i++)

{

if(i!=x)

{

do

{       

printf("\n enter the distance to node %d=",i+1);

scanf("%d",&n[x].t[i][2]);

}

while(n[x].t[x][2]<0||n[x].t[i][2]>999);

if(n[x].t[i][2]!=999)        

n[x].t[i][3]=i;

}

}

}

void caller(int no,int x)

{

void compar(int,int,int);

int i;

for(i=0;i<no;i++)

{

if(n[x].t[i][2]!=999&&n[x].t[i][2]!=0)

compar(x,i,no);

}

}

void compar(int x,int y,int no)

{

int i,z;

for(i=0;i<no;i++)

{

z=n[x].t[y][2]+n[y].t[i][2];

if(n[x].t[i][2]>z)

{

n[x].t[i][2]=z;

n[x].t[i][3]=y;

}

}

}

void op(int no,int x,int z)       

{

int i,j;

printf("\nthe routing table for node %d is as follows",x+1);

printf("\n\n\t\t\tDESTINATION\tDISTANCE\tnext hop");

for(i=0;i<no;i++)                    

{

if((!z&&n[x].t[i][2]>=999||n[x].t[i][2]>=(999*no)))

printf("\n\t\t\t%d\tno link\t\tnext hop",n[x].t[i][1]+1);

else

{

if(n[x].t[i][3]==NUL)

printf("\n\t\t\t%d\t\t%d\t\tno hop",n[x].t[i][1]+1,n[x].t[i][2]);

else

printf("\n\t\t\t%d\t\t%d\t\t%d",n[x].t[i][1]+1,n[x].t[i][2],n[x].t[i][3]+1);

}

}

}

void find(int x,int y)

{

int i,j;

i=x-1;

j=y-1;

printf("%d-->",x);

if(n[i].t[j][3]!=j)

{

find(n[i].t[j][3]+1,y);

return;

}

}