Count the Number of Ideal Arrays LeetCode solution in C++

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int comb[10001][14] = {1}, cnt[10001][14] = {}, mod = 1000000007;
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class Solution {
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 public:
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  int idealArrays(int n, int maxValue) {
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    if (comb[1][1] == 0) {             // one-time computation.
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      for (int s = 1; s <= 10000; ++s) // nCr (comb)
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        for (int r = 0; r < 14; ++r)
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          comb[s][r] = r == 0 ? 1 : (comb[s - 1][r - 1] + comb[s - 1][r]) % mod;
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      for (int div = 1; div <= 10000; ++div) { // Sieve of Eratosthenes
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        ++cnt[div][0];
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        for (int i = 2 * div; i <= 10000; i += div)
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          for (int bars = 0; cnt[div][bars]; ++bars) cnt[i][bars + 1] += cnt[div][bars];
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      }
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    }
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    int res = 0;
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    for (int i = 1; i <= maxValue; ++i)
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      for (int bars = 0; bars < min(14, n) && cnt[i][bars]; ++bars)
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        res = (1LL * cnt[i][bars] * comb[n - 1][bars] + res) % mod;
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    return res;
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  }
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};