Program to Add two long positive intergers

struct node
{
int data;
struct node*next;
};
void insert(struct node**p,int num)
{
struct node*temp;
if(*p==NULL)
{
(*p)=(struct node*)malloc(sizeof(struct node));
(*p)->next=NULL;
(*p)->data=num;
}
else
{
temp=(struct node*)malloc(sizeof(struct node));
temp->next=(*p);
(*p)=temp;
(*p)->data=num;
}
}


void add_in(struct node*a,struct node*b,struct node**c)
{
int d,carry;
carry=0;
struct node*t;
while(a!=NULL&&b!=NULL)
{
d=(a->data+b->data+carry)%10;
insert(c,d);
if( (a->data+b->data+carry) >= 10)
{
carry=1;
}
else carry=0;
a=a->next;
b=b->next;
}
if(a==NULL&&b==NULL)
{
return;
}
else
{
if(a!=NULL&&b==NULL)
{
t=a;
}
else
{
t=b;
}
while(t!=NULL)
{
d=(carry+t->data)%10;
if((carry+t->data)>=10)
carry=1;
else
carry=0;
insert(c,d);
t=t->next;
}
if(carry==1)
insert(c,carry);
}
}
void numin(struct node**p)
{
*p=NULL;char c='c';
while(c!='n')
{
c=getch();
if(!isdigit(c))
return;
else
{
putch(c);
insert(p,c-'0');
}
}
}
void disp(struct node*p)
{
if(p==NULL)
return;
else
{
printf("%d",p->data);
disp(p->next);
}

}
void main()
{
struct node *a,*b,*c;
clrscr();
a=b=c=NULL;
printf("Enter the first number....
");
numin(&a);
printf("
Enter the second number....
");
numin(&b);
printf("
The added result is...
");
add_in(a,b,&c);
disp(c);
getch();
}

Related Links :