Tuesday, 8 November 2016

C Programs

11/08/2016    




sum of digits in a number

#include <stdio.h>
#include <stdlib.h>

int main()
{
    int num,rem=0,sum=0;
    printf("enter number : ");
    scanf("%d",&num);
    while(num!=0)
    {
       rem=num%10;
       sum=sum+rem;
       num=num/10;
    }
    printf("sum of integer is : %d",sum);
    printf("\n");
} 





odd or even

 #include <stdio.h>
#include <stdlib.h>

int main()
{
   int num=0;
   printf("enter the number :");
   scanf("%d",&num);
   num=num%2;
   if(num==0)
   {
     printf("number is even ");
   }
   else
   {
       printf("number is odd");
   }
}




day equivalents

 #include <stdio.h>
#include <stdlib.h>

int main()
{
    int total_days=0,b1=0,year=0,week=0,day=0;
    printf("enter days : ");
    scanf("%d",&total_days);
    year=total_days/365;
    b1=total_days-(year*365);
    week=b1/7;
    day=b1-(week*7);
    printf("years=%d,week=%d,days=%d \n",year,week,day);
}





binary to decimal

#include <stdio.h>
#include <stdlib.h>
int main()
{
   int num,rem=0,dec=0,base=1;
   printf("enter binary number : ");
   scanf("%d",&num);
   while(num>0)
   {
       rem=num%10;
       dec=dec+(rem*base);
       base=base*2;
       num=num/10;
   }
   printf("decimal number is : %d ",dec);
}



decimal to binary


 #include <stdio.h>
#include <stdlib.h>

int main()
{
   int num,rem=0,bin=0,base=1,dec;
   printf("enter decimal number : ");
   scanf("%d",&dec);
   while(dec!=0)
   {
       rem=dec%2;
       bin=bin+(rem*base);
       base=base*10;
       dec=dec/2;
   }
   printf("corresponding binary= %d\n",bin);

}

number of 1s

#include<stdio.h>
int main()
{
    int n,result,count=0;
    printf("enter the number : ");
    scanf("%d",&n);
     while (n)
    {
      n &= (n-1) ;
      count++;
    }
    printf("number of 1's in the number = %d\n",count);
}


Description

9 = 1001 so there is total 2 number of 1s in 9


position of 1s



#include <stdio.h>
#include <stdlib.h>

int main()
{
    int num=0,check=0,i=0;
    printf("enter the number=");
    scanf("%d",&num);
    printf("1's in\n");
    for( i=0;i<9;i++)
    {
      if(num&(0x80>>i))
       {

           printf("position %d\n",i+1);
       }
    }
}


Description
Here we enter the number 9 = 00001001 ( 8 bit binary equivalent of 9 ) . So here in this example from LSB to MSB 1's in the position 5 and 8.

Pointers 

sum of array

 #include <stdio.h>
#include <stdlib.h>
int main()
{
   int num[11],*ptr,sum=0,i;
   printf("enter 10 elements : \n");
   for(i=0;i<10;i++)
   {
         printf("element %d=",(i+1));
         scanf("%d",&num[i]);   // exit from scanf() only when press enter key
   }
   ptr=&num;
   for(i=0;i<10;i++)
   {
       sum=sum+*ptr;
       ptr++;
   }
   printf("sum of array elements = %d\n",sum);
}

 

swapping

#include <stdio.h>
#include <stdlib.h>
int main()
{
   int num1,num2;
   printf("enter first number:");
   scanf("%d",&num1);
   printf("enter second number:");
   scanf("%d",&num2);
   swap(&num1,&num2);
   printf("\nswapped result is\n");
   printf("first number=%d\n",num1);
   printf("second number=%d\n",num2);
}
int swap(int *ptr1,int *ptr2)
{
    int reg;
    reg=*ptr1;
    *ptr1=*ptr2;
    *ptr2=reg;
}

reverse

#include<stdio.h>
int main()
{
    int num,rem,rev=0;
    printf("enter the number : ");
    scanf("%d",&num);
    while(num>0)
    {
        rem=num%10;
        rev=rev*10+rem;
        num=num/10;
    }
    printf("The reverse of number = %d\n",rev);
}


length of a string

#include <stdio.h>
#include <stdlib.h>
int main()
{
   char str[20],length=0;
   printf("enter the string=");
   gets(str);
   length=string_length(&str);
   printf("length of string=%d",length);
   length=0;
}
string_length(char *ptr)
{
    int num=0;
    while(*ptr!='\0')
    {
        num++;
        ptr++;
    }
    return num;
}