BASIC Programs in C

1. LARGEST OF THREE

#include<stdio.h>
#include<conio.h>
main()
{
int a,b,c,res;
clrscr();
printf("Enter the value of A,B and C: ");
scanf("%d %d %d",&a,&b,&c);
printf("The Largest Number is %d",res=( a>b ? (a>c?a:c) : (b>c?b:c) ) );
//ternary operator – cond ? true stmt : false stmt;
getch();
}

2. FIBNO

#include<stdio.h>
#include<conio.h>
main()
{
int i,f1,f2,f3,n;
clrscr();
printf("Enter the value of n: ");
scanf("%d",&n);
f1=0; f2=1;
for(i=1;i<=n;i++)
{
printf(" %d",f1);
f3=f1+f2;
f1=f2;
f2=f3;

}
getch();
}

3. FACTORIAL

#include<stdio.h>
#include<conio.h>
void main()
{
int i,n,fact=1;
printf(“Enter the number:”);
scanf(“%d”,&n);
for(i=1;i<=n;i++)
{
fact=fact*i;
}
printf(“The factorial of %d is %d ”,n,fact );
getch();
}
4. SWAPPING

#include<stdio.h>
#include<conio.h>
void main()
{
int x,y;

printf("\nEnter the value of A and B: ");

x=x+y; //swapping without using temporary variable

#include<stdio.h>
#include<conio.h>
void main()
{
int i,n;
clrscr();
printf("\nEnter the value of n : ");
scanf("%d",&n);
if(n==1)
{ printf("it is neither prime nor composite");
}
else
{
for(i=2 ; i<=(n/2) ;i++)
{
if ( (n%i)==0)
{
break;
}
}
if ( i > (n/2))
printf ("\nPrime");
else
printf ("\nNot Prime");
}
getch();
}

6. MAX MIN

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

void main()
{
int a[50],i,n,max,min;
printf("Enter the number of elements:");
scanf("%d",&n);
printf("Enter the elements:");
for(i=0;i<n;i++) // getting the input array
{
scanf("%d",&a[i]);
}
min=a[0]; // initializing min with first value in the array
max=a[0]; // initializing max with first value in the array
for(i=0;i<n;i++)
{
if( a[i]>max ) // updating the max value if necessary
{
max=a[i];
}
if( a[i]<min ) // updating the min value if necessary
{
min=a[i];
}
}
printf("\n The max number is %d",max);
printf("\n The min number is %d",min);
getch();
}

7. STRING COPY WITHOUT STRCPY

#include<stdio.h>
#include<conio.h>
void main()
{
int i;
char a[20],b[20];
printf("Enter the string:");
scanf("%s",a);
for(i=0; a[i] != '\0' ; i++ ) // loop will be executed until it finds the null character
{
b[i]=a[i]; // copying the characters one by one from a to b
}
b[i]='\0';
printf("The new string is %s",b);
getch();
}

8. LINEAR SEARCH

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

void main()
{
 int a[50],i,n,j,x,flag=0;
clrscr();
printf ("\nEnter the value of n : ");
scanf ("%d",&n);
printf ("\nENTER THE ARRAY : ");
for (i=1;i<=n;i++)
scanf ("%d",&a[i]);
printf ("\nENTER THE NUMBER TO BE SEARCH : ");
scanf ("%d",&x);
for (i=1;i<=n;i++)
{
if (x==a[i])
{
printf ("\n THE NUMBER IS FOUND AT POSITION: %d",i);
flag =1;
break;

}
}
if (flag==0)
printf ("\nTHE NUMBER IS NOT FOUND ");
getch();
}

9. PALINDROME

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

void main()
{
int i,n;
clrscr();
char a[20];
printf("Enter the string:");
scanf("%s",a);
n=0;
for(i=0; a[i]!='\0' ; i++ ) // finding the length of the string
{
n++;
}
n=n-1; // this statement can be omitted if n is initialized to -1
for(i=0; i<=n/2 ; i++)
{
if(a[i] != a[n-i]) //comparing the characters 0 and n , 1 and n-1 , 2 and n-2,..
{
printf("\n %s is not a palindrome",a );
break;
}
}
if(i>n/2) // checking whether the for loop has executed fully
{
printf("\n %s is a palindrome",a );
}
}
15. ARMSTRONG NUMBER

#include <stdio.h>

int main()
{
int x[10],a,b,n,i=0,j=0,temp,result;
printf("Enter the number:");
scanf("%d",&a);
b=a; //creating a copy of the input
n=0;
while(b>0) //finding the digits in the given number and storing them in array x.
{
n++;
x[i]=b%10;
i++;
b=b/10;
}
result=0;//initializing result to 0
for(i=0;i<n;i++) // loop to process digits
{
temp=1;
for(j=0;j<n;j++) // loop to find each digit raised to the power of no. of digits
{ // (eg.153 – 1^3, 5^3, 3^3 ; 1634 – 1^4 , 6^4 , 3^4 , 4^4 )
temp=temp*x[i];
}
result=result+temp;
}
if(result==a)
{
printf("%d is an Armstrong number",a);
}
else
{
printf("%d is not an Armstrong number",a);
}

return 0;
}

11. STRING COUNT

#include <stdio.h>
#include <conio.h>
#include <string.h>
#include <ctype.h>
void main(void)
{
int i,s=0,c=0,w=0,v=0,ch=0,d=0;
char name[500];
clrscr();
 printf ("\nENTER THE STRING : ");
gets(name);
for (i=0;name[i]!='\0';i++)
{
ch++;
if ((name[i]=='a'||name[i]=='e'||name[i]=='i'||name[i]=='o'||name[i]=='u')|| (name[i]=='A'||name[i]=='E'||
name[i]=='I'||name[i]=='O'||name[i]=='U'))
v++;

else if ((name[i]>='a' && name[i]<='z') || (name[i] >='A' && name[i]<='Z'))