Following program will also divide the number by 3:
- Code: Select all
int divideby3 (int num)
{
int sum = 0;
while (num > 3) {
sum += num >> 2;
num = (num >> 2) + (num & 3);
}
if (num == 3) ++sum;
return sum;
For example if your number is 10 then convert to binary
10=>00001010
if 10 > 3 then shift the binary number 2 bits
Now num will be 00000010 ie, 2
Now sum will be 2
num=(shift the number by 2 bits)+(number BITWISE AND 3)
num= 2+2
Now the number will be 4 then, 4>3 => true so loop will be repeated
4=>00000100 then shift the binary number 2 bits
Now sum=2+1 ie, sum=3
num=(shift the number(00000100) by 2 bits)+(number BITWISE AND 3)
num=1+0
ie remainder=1