For a given positive number we need to divide a number by 3 without using any of these *, /, +, – % operators

Examples:

Input : 48 Output : 16 Input : 16 Output : 5

**Algorithm**

- Take a number num, sum = 0
- while(num>3), shift the number left by 2 bits and sum = add(num >> 2, sum). Create a function add(x, y) for adding two number by bitwise opreator
- Take x, y
- run a do while loop till a is not zero
- a = x & y, b = x ^ y;, y = b;
- after terminating loop return value of b which gives sum of x and y

- Take bitwise AND of num with 3

for new num = add( num >> 2, num & 3) - After terminating while loop print the value of sum which give final result .

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 i.e, 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 (this value is returned)

num = (shift the number(00000100) by 2 bits) + (number BITWISE AND 3)

num = 1 + 0

ie remainder = 1

`// C++ program for divided a number by` `// 3 without using operator` `#include <bits/stdc++.h>` `using` `namespace` `std;` ` ` `// A function to add 2 numbers without using +` `int` `add(` `int` `x, ` `int` `y)` `{` ` ` `int` `a, b;` ` ` `do` `{` ` ` `a = x & y;` ` ` `b = x ^ y;` ` ` `x = a << 1;` ` ` `y = b;` ` ` `} ` `while` `(a);` ` ` ` ` `return` `b;` `}` ` ` `// Function to divide by 3` `int` `divideby3(` `int` `num)` `{` ` ` `int` `sum = 0;` ` ` ` ` `while` `(num > 3) {` ` ` `sum = add(num >> 2, sum);` ` ` `num = add(num >> 2, num & 3);` ` ` `}` ` ` ` ` `if` `(num == 3)` ` ` `sum = add(sum, 1);` ` ` ` ` `return` `sum;` `}` ` ` `// Driver program` `int` `main(` `void` `)` `{` ` ` `int` `num = 48;` ` ` `cout << ` `"The number divided by 3 is "` `;` ` ` `cout << divideby3(num);` ` ` ` ` `return` `0;` `}` |

**Output:**

The number divided by 3 is 16

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