Dice Combinations

#include <bits/stdc++.h>
using namespace std;
#define N 10000000
#define MOD 1000000007

typedef long long ll;

ll arr[N] = {
    0,
};

int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);

  int n;
  cin >> n;

  for (int i = 1; i <= n; i++) {
    if (i <= 6) {
      arr[i] += 1;
    }

    arr[i] += arr[i - 1];
    if (i - 2 >= 1) {
      arr[i] += arr[i - 2];
      arr[i] %= MOD;
    }
    if (i - 3 >= 1) {
      arr[i] += arr[i - 3];
      arr[i] %= MOD;
    }
    if (i - 4 >= 1) {
      arr[i] += arr[i - 4];
      arr[i] %= MOD;
    }
    if (i - 5 >= 1) {
      arr[i] += arr[i - 5];
      arr[i] %= MOD;
    }
    if (i - 6 >= 1) {
      arr[i] += arr[i - 6];
      arr[i] %= MOD;
    }
  }

  cout << arr[n] << endl;
  return 0;
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED

Test 16

Verdict: ACCEPTED

Test 17

Verdict: ACCEPTED

Test 18

Verdict: ACCEPTED

Test 19

Verdict: ACCEPTED

Test 20

Verdict: ACCEPTED