Check if a number has bits in alternate pattern

Given an integer n > 0, the task is to find whether this integer has an alternate pattern in its bits representation. For example- 5 has an alternate pattern i.e. 101.
Print “Yes” if it has an alternate pattern otherwise “No”. Here alternate pattern can be like 0101 or 1010.


Input :  15
Output :  No
Explanation: Binary representation of 15 is 1111.

Input :  10
Output :  Yes
Explanation: Binary representation of 10 is 1010.

A simple approach is to find its binary equivalent and then check its bits.

// C++ program to find if a number has alternate
// bit pattern
using namespace std;

// Returns true if n has alternate bit pattern
// else false
bool findPattern(int n)
    // Store last bit
    int prev = n % 2;
    n = n/2;

    // Traverse through remaining bits
    while (n > 0)
        int curr = n % 2;

        // If current bit is same as previous
        if (curr == prev)
           return false;

        prev = curr;
        n = n / 2;

    return true;

// Driver code
int main()
    int n = 10;
    if (findPattern(n))
        cout << "Yes";
        cout << "No";

    return 0;




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