This C program converts a decimal number to binary by using bitwise operators to iterate through each bit position from most significant to least significant. It uses a right shift operator to test each bit and prints a 1 or 0 accordingly, outputting the binary representation of the decimal number entered by the user.

1. C program to find hcf and lcm
#include<stdio.h>
//#include<conio.h>
int main()
{
int n, c, k;
printf("Enter an integer in decimal number systemn");
scanf("%d", &n);
printf("%d in binary number system is:n", n);
for (c = 31; c >= 0; c--)
{
k = n >> c;
if (k & 1)
printf("1");
else
printf("0");
}
printf("n");
return 0;
}
Output of program: