The bitwise operator can be used to multiply a value by seven. Subtract the original number from the shifted number and return the difference (8n – n) by left shifting the number by 3 bits (you’ll receive 8n).

Give a number the task is to get the multiplication of the given number by 7 in an efficient way.

**Examples:**

**Example1:**

**Input:**

Given Number = 5

**Output:**

After multiplying the given number{ 5 } by 7 = 35

**Example2:**

**Input:**

Given Number = 3

**Output:**

After multiplying the given number{ 3 } by 7 = 21

## Program for Efficient Way to Multiply With 7 in Python

Below are the ways to get the multiplication of the given number by 7 in an efficient way in Python:

### Method #1: Using Left Shift (<<) Operator (Static Input)

**Approach:**

- Create a recursive function to say
**effcnt_mult_bysevn()**which takes the given number as an argument and returns the result of the given number multiplied by 7 in an efficient way. - Inside the
**effcnt_mult_bysevn****()**function. - Calculate and the value of (gvn_numb << 3) – gvn_numb which gives the multiplication of the given number by 7 and store it in a variable say
**rslt_mult**. - Return the value of
**rslt_mult**(Which is the multiplication of the given number by 7). - Inside the main code.
- Give the number as static input and store it in a variable.
- Pass the given number as the argument to
**effcnt_mult_bysevn****()**function and store the result in a variable (**fnl_rslt**). - Print the
**fnl_rslt**value. - The Exit of the Program.

**Below is the implementation:**

# Create a recursive function to say effcnt_mult_bysevn() which takes the given number # as an argument and returns the result of the given number multiplied by 7 in an # efficient way. def effcnt_mult_bysevn(gvn_numb): # Inside the effcnt_mult_bysevn () function. # Calculate and the value of (gvn_numb << 3) - gvn_numb which gives the multiplication # of the given number by 7 and store it in a variable say rslt_mult. rslt_mult = (gvn_numb << 3) - gvn_numb # Return the value of rslt_mult(Which is the multiplication of the given number by 7). return (rslt_mult) # Inside the main code. # Give the number as static input and store it in a variable. gvn_numb = 5 # Pass the given number as the argument to effcnt_mult_bysevn() function and # store the result in a variable (fnl_rslt). fnl_rslt = effcnt_mult_bysevn(gvn_numb) # Print the fnl_rslt value. print("After multiplying the given number{", gvn_numb, "} by 7 = ", fnl_rslt)

**Output:**

After multiplying the given number{ 5 } by 7 = 35

### Method #2: Using Left Shift (<<) Operator (User Input)

**Approach:**

- Create a recursive function to say
**effcnt_mult_bysevn()**which takes the given number as an argument and returns the result of the given number multiplied by 7 in an efficient way. - Inside the
**effcnt_mult_bysevn****()**function. - Calculate and the value of (gvn_numb << 3) – gvn_numb which gives the multiplication of the given number by 7 and store it in a variable say
**rslt_mult**. - Return the value of
**rslt_mult**(Which is the multiplication of the given number by 7). - Inside the main code.
- Give the number as user input using the int(input()) function and store it in a variable.
- Pass the given number as the argument to
**effcnt_mult_bysevn****()**function and store the result in a variable (**fnl_rslt**). - Print the
**fnl_rslt**value. - The Exit of the Program.

**Below is the implementation:**

# Create a recursive function to say effcnt_mult_bysevn() which takes the given number # as an argument and returns the result of the given number multiplied by 7 in an # efficient way. def effcnt_mult_bysevn(gvn_numb): # Inside the effcnt_mult_bysevn () function. # Calculate and the value of (gvn_numb << 3) - gvn_numb which gives the multiplication # of the given number by 7 and store it in a variable say rslt_mult. rslt_mult = (gvn_numb << 3) - gvn_numb # Return the value of rslt_mult(Which is the multiplication of the given number by 7). return (rslt_mult) # Inside the main code. # Give the number as user input using the int(input()) function and store it in a variable. gvn_numb = int(input('Enter some random number = ')) # Pass the given number as the argument to effcnt_mult_bysevn() function and # store the result in a variable (fnl_rslt). fnl_rslt = effcnt_mult_bysevn(gvn_numb) # Print the fnl_rslt value. print("After multiplying the given number{", gvn_numb, "} by 7 = ", fnl_rslt)

**Output:**

Enter some random number = 3 After multiplying the given number{ 3 } by 7 = 21