func_code_string: #include <bits/stdc++.h>   using namespace std;   const int N = 35;   const int MOD = 1e9 + 7;   long long n;   int K, c, res;   struct mat {     int d[N][N];     mat() { memset(d, 0, sizeof d); }   } F[N * 2][N], P[N * 2][N], Q[N * 2][N], G;   int lst[N * 2];   mat operator*(mat a, mat b) {     mat c;     for (int i = 0; i <= K; ++i)       for (int j = 0; j <= K; ++j)         for (int k = 0; k <= K; ++k)           c.d[i][k] = (c.d[i][k] + 1ll * a.d[i][j] * b.d[j][k]) % MOD;     return c;   }   int main() {     cin >> n >> K;     while (n) lst[c++] = n % K, n /= K;     for (int i = 0; i < c; ++i) {       if (i == 0) {         for (int j = 0; j < K; ++j) {           for (int p = 0; p < K; ++p) F[i][j].d[p][p] = 1;           for (int p = 0; p <= K; ++p) F[i][j].d[j][p] = 1;           F[i][j].d[K][K] = 1;         }       } else {         for (int j = 1; j < K; ++j) F[i][j] = Q[i - 1][j] * P[i - 1][j - 1];         F[i][0] = Q[i - 1][0];       }       P[i][0] = F[i][0];       for (int j = 1; j < K; ++j) P[i][j] = P[i][j - 1] * F[i][j];       Q[i][K - 1] = F[i][K - 1];       for (int j = K - 2; ~j; --j) Q[i][j] = F[i][j] * Q[i][j + 1];     }     for (int i = 0; i <= K; ++i) G.d[i][i] = 1;     for (int i = c - 1, s = 0; ~i; --i) {       for (int j = 0; j < lst[i]; ++j) G = G * F[i][(s + j) % K];       s = (s + lst[i]) % K;     }     res = 1;     for (int i = 0; i < K; ++i) res = (res + G.d[i][K]) % MOD;     cout << res << endl;   }   