# Check if a number can be expressed as power in C++

C++Server Side ProgrammingProgramming

Here we will check whether we can represent a number as power, like ab or not. Suppose a number 125 is present. This can be represented as 53. Another number 91 cannot be represented as power of some integer value.

## Algorithm

isRepresentPower(num):
Begin
if num = 1, then return true
for i := 2, i2 <= num, increase i by 1, do
val := log(a)/log(i)
if val – int(val) < 0.0000000001, then return true
done
return false
End

## Example

Live Demo

#include<iostream>
#include<cmath>
using namespace std;
bool isRepresentPower(int num) {
if (num == 1)
return true;
for (int i = 2; i * i <= num; i++) {
double val = log(num) / log(i);
if ((val - (int)val) < 0.00000001)
return true;
}
return false;
}
int main() {
int n = 125;
cout << (isRepresentPower(n) ? "Can be represented" : "Cannot be represented");
}

## Output

Can be represented
Published on 27-Sep-2019 08:31:32