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enh(CPlusPlus): add missing space to power-of-two maths (#667) 

Co-authored-by: Rahul Rajeev Pillai <66192267+Ashborn-SM@users.noreply.github.com>
Co-authored-by: datshan-trivedi-10 <dbtrivedi03@gmail.com>
pull/540/head^2
Darshan Trivedi 2022-01-13 18:29:14 +05:30 committed by GitHub
parent 110518e7c6
commit f97cb54a2e
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1 changed files with 24 additions and 12 deletions
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36
algorithms/CPlusPlus/Maths/power-of-two.cpp
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@ -1,27 +1,37 @@
#include <iostream> #include <iostream>
using namespace std; using namespace std;
//function starts // function starts
bool isPowerOfTwo(const n) bool isPowerOfTwo(const int n)
{ {
//declare a variable to know if n is a power of 2 or not // declare a variable to know if n is a power of 2 or not
long i = 1; long i = 1;
//at every iteration it will calcalute power of 2 starting from 1 // at every iteration it will calcalute power of 2 starting from 1
while (i < n) while (i < n)
{ {
i = i * 2; i = i * 2;
} }
//if n is the power of 2, i and n value will be same // if n is the power of 2, i and n value will be same
//if they are same, it will return true, else it will return false // if they are same, it will return true, else it will return false
return i == n; return i == n;
} }
//main starts // Binary Method to check number is in power of two or not.
// Time Complexity of this method is O(1)
bool ispoweroftwo(const int n)
{
// if number is in power of two it will give 0, otherwise it will not zero.
return n != 0 && (n & (n - 1)) == 0;
}
// main starts
int main() int main()
{ {
int n; int n;
cin >> n; cin >> n;
cout << isPowerOfTwo(n); cout << isPowerOfTwo(n) << endl;
// Check using Binary Method
cout << ispoweroftwo(n) << endl;
return 0; return 0;
} }
@ -29,13 +39,15 @@ int main()
Example 1: Example 1:
Input: n = 1 Input: n = 1
Output:1 (true) Output:1 (true)
Explanation: 20 = 1 Explanation: 2^0 = 1
Example 2: Example 2:
Input: n = 16 Input: n = 16
Output:1 (true) Output:1 (true)
Explanation: 24 = 16 Explanation: 2^4 = 16
Example 3: Example 3:
Input: n = 3 Input: n = 3