Dice Combinations

input/code.cpp: In function 'void Test()':
input/code.cpp:16:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   16 |     freopen("temp\\in.txt", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
input/code.cpp: In function 'int main()':
input/code.cpp:22:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   22 |     scanf("%d", &n);
      |     ~~~~~^~~~~~~~~~

#include<iostream>
#include<cstdio>
#include<algorithm>
typedef long long LL;

const int N=1000006, M=1e9+7;
int f[N], sum[N];

inline int Add(const int& a, const int& b)
{
    return (a+b)%M;
} //add big num with mod

void Test()
{
    freopen("temp\\in.txt", "r", stdin);
}
int main()
{
    // Test();
    int n;
    scanf("%d", &n);

    f[1]=1, sum[1]=1;
    for(int i=2; i<=6; i++)
    {
        f[i] = f[i-1]*2;
        sum[i] = Add(sum[i-1], f[i]);
    }

    for(int i=7; i<=n; i++)
    {
        f[i] = sum[i-1] - sum[i-7];
        if(f[i] < 0) f[i] += M;
        sum[i] = Add(sum[i-1], f[i]);
    }

    printf("%d", f[n]);

    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