Minimum Non-Zero Product of the Array Elements LeetCode solution in C++

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class Solution {
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 public:
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  long long myPow(long long base, long long exponent, long long mod) {
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    if (exponent == 0) return 1;
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    if (exponent == 1) return base % mod;
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    long long tmp = myPow(base, exponent / 2, mod);
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    if (exponent % 2 == 0) { // (base ^ exponent/2) * (base ^ exponent/2)
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      return (tmp * tmp) % mod;
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    } else { // (base ^ exponent/2) * (base ^ exponent/2) * base
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      tmp = tmp * tmp % mod;
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      base %= mod;
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      return (tmp * base) % mod;
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    }
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  }
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  int minNonZeroProduct(int p) {
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    long long range = pow(2, p);
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    range--;
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    long long mod = pow(10, 9) + 7;
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    long long tmp = myPow(range - 1, range / 2, mod);
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    return (tmp * (range % mod)) % mod;
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  }
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};