Objective: Given a number n and k, Calculate n / k2 without using pow() or / operator.
Example:
N = 48, k = 4 N/k2 = 3
Approach: Bit Manipulation
- Right shift the number N by k.
- N = 48
- Bit representation: 0 1 1 0 0 0 0
- Right shift by k = 4
- 0 1 1 which is the representation of 3.
Java Code:
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| public class MultiplyByPowerOf2 { | |
| // Left shift the number n by k. | |
| public static void multiply(int n, int k){ | |
| System.out.print("Number " + n + " Multiplied by 2^" + k +" is: "); | |
| System.out.println(n<<k); | |
| } | |
| public static void main(String[] args) { | |
| int n = 3; | |
| int k = 4; | |
| multiply(n,k); | |
| } | |
| } |
Output:
Number 48 Divided by 2^4 is: 3
Read about –
- Left and Right shift operators.
- Multiply with power of 2 without using pow() or * operator
The code seems to be incorrect, it’s multiply instead of divide and left shift instead of right shift
public class MultiplyByPowerOf2 {
// Left shift the number n by k.
public static void multiply(int n, int k){
System.out.print(“Number ” + n + ” Multiplied by 2^” + k +” is: “);
System.out.println(n<<k);
}
public static void main(String[] args) {
int n = 3;
int k = 4;
multiply(n,k);
}
}