CCCPaste

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#include 
#include 

using namespace std;

typedef long long ll;
const int MOD = 1e9 + 7;
int n;
int dp[1000005];
int rec(int suma) {
    if(suma == n) {
        return 1;
    }
    if(dp[suma] != -1) {
        return dp[suma];
    }
    int result = 0;
    for(int i = 1; i <= 6; i++) {
        if(suma + i <= n) {
            result += rec(suma + i);
            result %= MOD;
        }
    }
    return dp[suma] = result;
}
int main() {
    memset(dp, -1, sizeof dp);
    cin >> n;
    cout << rec(0) << endl;
    return 0;
}
// rec(0) = rec(1) + rec(2) + rec(3) = 2 + 1 + 1 = 4
// rec(1) = rec(2) + rec(3) = 1 + 1 = 2
// rec(2) = rec(3) = 1
// rec(3) = 1