Pathshala Code Book

#include <stdio.h>

int main(int argc,char *argv[])
{

if(argc==1){
printf("Error:Please enter atleast one argument");
return 0;
}

//Note:- argv[0] is by default 0 our input string start storing from argv[1]. So it's better to start for loop from 1

int i,v=0,size=argc-1;

char *str;//intialize pointer

//allocate memory to which pointer points

str=(char*)malloc(v);//intially zero

//now re allocate memory as per size of input sting arguments
for(i=1;i<=size;i++){

int length=v+strlen(argv[i]);
str=(char*)realloc(str,length);

//now concatenate the string argument
strcat(str,argv[i]);
//give a namespace
strcat(str," ");
}

//now print string use %s not %concatenate
printf("%s\n",str);

return 0;


}

#include<stdio.h>
#include<stdlib.h>
#include<malloc.h>
struct node{
   int label;
   char oper;
   int address;
   struct node *next;
};
//shorting the name
typedef struct node node;

node *head;

//Display function
void display(){
   if(head==NULL)
   {
       printf("There is no node \n");
   }
   //Create temporary node t
   node *t=head;

   while(t){
       printf("%d\t",t->label);

       printf("%c\t",t->oper);

       printf("%d\t",t->address);

       t=t->next;
   }

}

//Insert function
void insert(){

   int a,c;
   char b;

   //create new node
   node *nnode=(node*) malloc(sizeof(node));
   printf("Enter Label,Operator,Address\n\n");

   scanf("%d",&a);//Label
   getchar();
   scanf("%c",&b);//oper
   getchar();
   scanf("%d",&c);//address
   getchar();
   printf("\n");
   nnode->label=a;
   nnode->oper=b;
   nnode->address=c;

   if(head==NULL){
       nnode->next=NULL;
       head=nnode;
   }
   else{
       //insert at the end
       node *t=head;
       while(t->next){
           //traverse until t->next=NULL
           t=t->next;
       }

       t->next=nnode;//New node will be inserted at the end
       nnode->next=NULL;


   }
}

void remove(int l){

   node *t=head;//store head so it do not change
   node *p;
   p=t;//Take head address to temp pointer to remove it

   if(head==NULL){
       printf("There is nothing to delete\n\n");

       return;
   }
   if (t!=NULL && t->label==l){
       //This is single or first node to delete t->NULL
   free(t);
   head=NULL;
       return;

   }

   while(t->next!=NULL && t->label!=l){
       p=t;
       t=t->next;
   }

   if(t==NULL){
       printf("Item is not available\n\n");
       return;
   }

/*   if(t->label==l)
   {
       head=t->next;
       free(t);
       return;
   }*/
   p->next=t->next;
   free(t);

   return;
}

int main(){

   int l,ch;

   do{
       printf("*Enter Your choice*\n1.Insert Node\t2.Display List\t3.Delete Node\t4.Exit\n");

       printf("Choice:\t");scanf("%d",&ch);printf("\n");

       switch(ch){
           case 1:
               insert();
               break;

               case 2:
                   printf("Display:-");
                   display();
                   printf("\n\n");
                   break;

                   case 3:
                       printf("Enter label to remove:-\t");
                       scanf("%d",&l);
                       remove(l);
                       break;

                       case 4:
                       exit(0);


           default:
               printf("Wrong choice try again\n");
       }
   }while(ch<=3);

}