c program to print the following pattern

#include<stdio.h>
#include<conio.h>
int main()
{ int a,c,b;
clrscr();
for(a=8;a>=2;a=a-2)
{
for(c=1;c<=a;c++)
{

printf("%d",c);
}
printf("\n");
}
getch();
}

c program to insert a node in the beginning of the linked list

#include <stdio.h>

#include <stdlib.h>

     struct Node{

     int data;

     struct Node *next;

     };

     struct Node* head;

     void Insert(int x)

     {

     struct Node* temp = (struct Node*)malloc(sizeof(struct Node));

     temp->data=x;

     temp->next = head;    

     head= temp;           

     }

     void Print()

     {

      struct Node * temp= head;

           printf("List is: ");

     while(temp != NULL)

      {

       printf("%d  ", temp->data);

      temp= temp->next;

     }

     printf("\n");

     }

    

     int main()

     {   

      head =NULL;

      int n, i, x;

    

     printf("How many Numbers?: \n");

     scanf("%d", &n);

     for(i= 0; i<n; i++)

     {

    printf("Enter the number: ");

    scanf("%d",&x);

     Insert(x);

    Print();

      }

      return 0;

     }

dynamic allocation of stack

#include <stdio.h>
#include <stdlib.h>
struct node
{int data;
 struct node *link;
}*top = NULL;
#define MAX 5
// function prototypes
void push();
void pop();
void empty();
void stack_full();
void stack_count();
void destroy();
void print_top();

void main()
{
    int choice;

    while (1)
    {
        printf("1. push an element \n");
        printf("2. pop an element \n");
        printf("3. check if stack is empty \n");
        printf("4. check if stack is full \n");
        printf("5. count/display elements present in stack \n");
        printf("6. empty and destroy stack \n");
        printf("7. Print top of the stack \n");
        printf("8. exit \n");
        printf("Enter your choice \n");
        scanf("%d",&choice);
        switch (choice)
        {
        case 1:   
            push();
            break;        
        case 2:   
            pop();
            break;        
        case 3:   
            empty();
            break;        
        case 4:   
            stack_full();
            break;        
        case 5:   
            stack_count();
            break;        
        case 6:   
            destroy();
            break;        
        case 7:   
            print_top();
            break;
        case 8:   
            exit(0);
        default:
            printf("wrong choice\n");        
        }
    }
}
// to insert elements in stack
void push()
{
    int val,count;
    struct node *temp;
    temp = (struct node*)malloc(sizeof(struct node));
    count = st_count();
    if (count <= MAX - 1)
    {
        printf("\nEnter value which you want to
            push into the stack :\n");
        scanf("%d",&val);
        temp->data = val;
        temp->link = top;
        top = temp;
    }
    else
        printf("WARNING: STACK FULL\n");
}
// to delete elements from stack
void pop()
{
    struct node *temp;
    if (top =  = NULL)
        printf("**Stack is empty**\n");
    else
    {
        temp = top;
        printf("Value popped out is %d \n",temp->data);
        top = top->link;
        free(temp);
    }
}
// to check if stack is empty
void empty()
{
    if (top =  = NULL)
        printf("STACK IS EMPTY\n");
    else
        printf("elements are present, stack
                   is not empty \n");
}
// to check if stack is full
void stack_full()
{
    int count;

    count = st_count();
    if (count =  = MAX)
    {
        printf("stack is full\n");
    }
    else
        printf("stack is not full \n");
}
// to count the number of elements
void stack_count()
{
    int count = 0;
    struct node *temp;

    temp = top;
    while (temp! = NULL)
    {
        printf(" %d\n",temp->data);
        temp = temp->link;
        count++;
    }
    printf("size of stack is %d \n",count);
}
int st_count()
{
    int count = 0;
    struct node *temp;
    temp = top;
    while (temp! = NULL)
    {
        temp = temp->link;
        count++;
    }
    return count;
}
// to empty and destroy the stack
void destroy()
{
    struct node *temp;
    temp = top;
    while (temp! = NULL)
    {
        pop();
        temp = temp->link;
    }
    printf("stack destroyed\n");
}
// to print top element of stack
void print_top()
{
    if (top == NULL)
        printf("\n**Top is not available for an EMPTY stack**\n");
    else
        printf("\nTop of the stack is %d \n",top->data);
}

C programming code for binary search

#include <stdio.h>
 
int main()
{
   int c, first, last, middle, n, search, array[100];
 
   printf("Enter number of elements\n");
   scanf("%d",&n);
 
   printf("Enter %d integers\n", n);
 
   for (c = 0; c < n; c++)
      scanf("%d",&array[c]);
 
   printf("Enter value to find\n");
   scanf("%d", &search);
 
   first = 0;
   last = n - 1;
   middle = (first+last)/2;
 
   while (first <= last) {
      if (array[middle] < search)
         first = middle + 1;    
      else if (array[middle] == search) {
         printf("%d found at location %d.\n", search, middle+1);
         break;
      }
      else
         last = middle - 1;
 
      middle = (first + last)/2;
   }
   if (first > last)
      printf("Not found! %d is not present in the list.\n", search);
 
   return 0;   
}

deleting an element from an array

#include<conio.h>
#include<stdio.h>
void main()
{
int a[20];
int n,val,i,pos;
clrscr();

        printf("\nEnter the size of the array elements:\t");
scanf("%d",&n);
 printf("\nEnter the elements for the array:\n");
for(i=0;i<n;i++)
{
scanf("%d",&a[i]);
}
 printf("\nEnter the position of the element to be deleted:\t");
scanf("%d",&pos);
val=a[pos];
for(i=pos;i<n-1;i++)
{
a[i]=a[i+1];
}
n=n-1;
printf("\nThe deleted element is =%d",val);
printf("\nThe array elements are:\n");
for(i=0;i<n;i++){
printf("%d\t",a[i]);
}
getch();
}

Adding an elements from an array

#include<stdio.h>
#include<conio.h>
void main()
{ int pos,val,i,a[100],n;
   clrscr();
   printf("enter elements of array");
   for(i=0;i<5;i++){
   scanf("%d",&a[i]); }
    printf("\nEnter the position for the new element:\t");
    scanf("%d",&pos);
    printf("\nEnter the element to be inserted :\t");
    scanf("%d",&val);
    for(i=5-1;i>=pos;i--)
{
a[i+1]=a[i];
}
a[pos]=val;
n=n+1;
printf("\nThe array elements are:\n");
for(i=0;i<=5;i++){
printf("%d\t",a[i]);
}

getch();

}

wap a code to show various operation on array like sum,max element ,min element,sum of positive and negative number and avg

#include<stdio.h>
#include<conio.h>
void main()
{
int i,j,sum=0,max=0,min=0,loc,n,neg_sum=0,pos_sum=0;
int a[100];
float avg=0;
clrscr();
printf("enter size of array\n");
scanf("%d",&n);
printf("enter %d elements\n",n);
for(i=0;i<n;i++)
scanf("%d",&a[i]);
for(i=0;i<n;i++){
sum=sum+a[i];
}
for(i=0;i<n;i++){
if(a[i]<0)
{
neg_sum=neg_sum+a[i];
}
else if(a[i]>0){
pos_sum=pos_sum+a[i];
}
}

avg=sum/n;
max=a[0];
for(i=0;i<n;i++){
if(a[i]>max){
max=a[i];
loc=i+1;
}
}
min=a[0];
for(i=0;i<n;i++){
if(a[i]<min){
min=a[i];
}
}

printf("entered elements are\n");
for(i=0;i<n;i++){
printf("%d\n",a[i]);}
printf("sum=%d\n",sum);
printf("pos_sum=%d\n",pos_sum);
printf("neg_sum=%d\n",neg_sum);
printf("avg=%f\n",avg);
printf("max element is at location=%d and val=%d\n",loc,max);
printf("min element=%d\n",min);
getch();
}

C program to find the second largest element in an array

#include<stdio.h>

#include<conio.h>

int main(){

  int a[50],size,i,j=0,big,secondbig;

  printf("Enter the size of the array: ");

  scanf("%d",&size);

  printf("Enter %d elements in to the array: ", size);

  for(i=0;i<size;i++)

      scanf("%d",&a[i]);

  big=a[0];

  for(i=1;i<size;i++){

      if(big<a[i]){

           big=a[i];

           j = i;

      }

  }

  secondbig=a[size-j-1];

  for(i=1;i<size;i++){

      if(secondbig <a[i] && j != i)

          secondbig =a[i];

  }

  

  printf("Second biggest: %d", secondbig);

  return 0;

}

Wap to draw a triangle

#include<stdio.h>
#include<conio.h>
#include<graphics.h>

void main() {

int gd = DETECT, gm;
initgraph(&gd, &gm, "c:\\tc\\bgi");

 line(300, 100, 200, 200);
line(300, 100, 400, 200);
line(200, 200, 400, 200);
getch();

closegraph();

}