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How to check if a number N is integer power of another number B
By Ishtiaq11, history, 9 years ago, In English

I have two integer b,n. I need to check if the number n is integer power of number b. For example: 100 is an integer power of 10. As 10^2 = 100. But 110 is not an integer power of 10. How to determine this in coding?

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9 years ago, hide # |
 
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Try to do like this:

Find log2 of n. Then divide it by log2 of b.

If the result is integer, then n is power of b.

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9 years ago, hide # |
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k=b
while(k<n){
  if((n/k)<b)break; // to avoid overflow
  k*=b
}
cout << ((k==n) ? "yes" : "no");
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