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@@ -0,0 +1,32 @@
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+#include <iostream>
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+#include <cstdint>
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+#include <cmath>
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+
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+class Solution {
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+public:
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+ bool isPowerOfThree(int n) {
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+ if ( n <= 0 ) { return false; }
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+ if ( n == 1 ) { return true; }
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+ for ( int i = 1; i < n; ++i ) {
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+ long val = pow(3, i);
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+ if ( val == n ) { return true; }
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+ if ( val > n ) { return false; }
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+ }
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+ return false;
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+ }
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+};
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+
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+void r(int n, bool exp) {
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+ std::cout << "Solution().isPowerOfThree(" << n << ") = ";
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+ std::cout << Solution().isPowerOfThree(n);
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+ std::cout << " | exp: " << exp << "\n";
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+};
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+
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+int main(void) {
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+ r(27, true);
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+ r(9, false);
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+ r(0, false);
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+ r(-1, false);
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+
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+ return 0;
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+}
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