Minimum number using set bits of a given number in C++

Problem statement

Given an unsigned number, find the minimum number that could be formed by using the bits of the given unsigned number.

Example

If input = 10 then answer would be 3

Binary representation of 10 is 1010 and minimum number with 2 set bits is 0011 i.e. 3

Algorithm

1. Count the number of set bits.
2. (Number of set bits) ^ 2 – 1 represents the minimized number)

Example

 Live Demo

#include <bits/stdc++.h>
using namespace std;
int getSetBits(int n) {
   int cnt = 0;
   while (n) {
      ++cnt;
      n = n & (n - 1);
   }
   return cnt;
}
int getMinNumber(int n){
   int bits = getSetBits(n);
   return pow(2, bits) - 1;
}
int main() {
   int n = 10;
   cout << "Minimum number = " << getMinNumber(n) << endl;
   return 0;
   return 0;
}

When you compile and execute above program. It generates following output

Output

Minimum number = 3

Narendra Kumar

Updated on 23-Dec-2019 06:12:59

• Related Questions & Answers
• Number of integers with odd number of set bits in C++
• Minimum flips required to maximize a number with k set bits in C++.
• Next higher number with same number of set bits in C++
• Convert a number m to n using minimum number of given operations in C++
• Check if a number has same number of set and unset bits in C++
• Reverse actual bits of the given number in Java
• Check if all bits of a number are set in Python
• Maximum number of contiguous array elements with same number of set bits in C++
• Prime Number of Set Bits in Binary Representation in C++
• Prime Number of Set Bits in Binary Representation in Python
• Check if bits of a number has count of consecutive set bits in increasing order in Python
• Minimum number of coins that make a given value
• C# program to count total set bits in a number
• For every set bit of a number toggle bits of other in C++
• Minimum number of squares whose sum equals to given number n