101621: [AtCoder]ABC162 B - FizzBuzz Sum

Problem Statement

Let us define the FizzBuzz sequence $a_1,a_2,...$ as follows:

• If both $3$ and $5$ divides $i$, $a_i=\text{FizzBuzz}$.
• If the above does not hold but $3$ divides $i$, $a_i=\text{Fizz}$.
• If none of the above holds but $5$ divides $i$, $a_i=\text{Buzz}$.
• If none of the above holds, $a_i=i$.

Find the sum of all numbers among the first $N$ terms of the FizzBuzz sequence.

Constraints

• $1 \leq N \leq 10^6$

Input

Input is given from Standard Input in the following format:

$N$

Output

Print the sum of all numbers among the first $N$ terms of the FizzBuzz sequence.

Sample Input 1

15

Sample Output 1

60

The first $15$ terms of the FizzBuzz sequence are:

$1,2,\text{Fizz},4,\text{Buzz},\text{Fizz},7,8,\text{Fizz},\text{Buzz},11,\text{Fizz},13,14,\text{FizzBuzz}$

Among them, numbers are $1,2,4,7,8,11,13,14$, and the sum of them is $60$.

Sample Input 2

1000000

Sample Output 2

266666333332

Watch out for overflow.