#include <bits/stdc++.h>
using namespace std;
const int MOD = 1073741824;
long long sol[1000001];
long long d(long long a) {
  if (sol[a] != 0) {
    return sol[a];
  }
  int i, c = 0;
  for (i = 1; i <= a / i; i++) {
    if (a % i == 0) {
      if (i * i != a) {
        c++;
      }
      c++;
    }
  }
  sol[a] = c;
  return c;
}
int main() {
  long long a, b, c, m = 0, sum = 0, i, j, v;
  cin >> a >> b >> c;
  for (i = 1; i <= a; i++)
    for (j = 1; j <= b; j++)
      for (v = 1; v <= c; v++) {
        sum += d(i * j * v);
      }
  cout << sum % MOD;
  return 0;
}

### Prompt

Please provide a cpp coded solution to the problem described below:

Let's denote d(n) as the number of divisors of a positive integer n. You are given three integers a, b and c. Your task is to calculate the following sum:

<image>

Find the sum modulo 1073741824 (230).

Input

The first line contains three space-separated integers a, b and c (1 ≤ a, b, c ≤ 2000).

Output

Print a single integer — the required sum modulo 1073741824 (230).

Examples

Input

2 2 2


Output

20


Input

4 4 4


Output

328


Input

10 10 10


Output

11536

Note

For the first example.

  * d(1·1·1) = d(1) = 1; 
  * d(1·1·2) = d(2) = 2; 
  * d(1·2·1) = d(2) = 2; 
  * d(1·2·2) = d(4) = 3; 
  * d(2·1·1) = d(2) = 2; 
  * d(2·1·2) = d(4) = 3; 
  * d(2·2·1) = d(4) = 3; 
  * d(2·2·2) = d(8) = 4. 



So the result is 1 + 2 + 2 + 3 + 2 + 3 + 3 + 4 = 20.

### Response

```cpp
#include <bits/stdc++.h>
using namespace std;
const int MOD = 1073741824;
long long sol[1000001];
long long d(long long a) {
  if (sol[a] != 0) {
    return sol[a];
  }
  int i, c = 0;
  for (i = 1; i <= a / i; i++) {
    if (a % i == 0) {
      if (i * i != a) {
        c++;
      }
      c++;
    }
  }
  sol[a] = c;
  return c;
}
int main() {
  long long a, b, c, m = 0, sum = 0, i, j, v;
  cin >> a >> b >> c;
  for (i = 1; i <= a; i++)
    for (j = 1; j <= b; j++)
      for (v = 1; v <= c; v++) {
        sum += d(i * j * v);
      }
  cout << sum % MOD;
  return 0;
}

```