solution.cpp

/*
    Topic : Algorithms
    Subtopic : Flipping bits
    Language : C++
    Problem Statement : 
      You will be given a list of 32 bit unsigned integers. Write a function to Flip all the bits (1 -> 0 and 0 -> 1) and return the result as an unsigned integer.
    Url : https://www.hackerrank.com/challenges/flipping-bits/problem
*/

#include <bits/stdc++.h>

using namespace std;

string ltrim(const string &);
string rtrim(const string &);

long BITS = (long)(pow(2, 32) - 1);

/*
 * Complete the 'flippingBits' function below.
 *
 * The function is expected to return a LONG_INTEGER.
 * The function accepts LONG_INTEGER n as parameter.
 */

long flippingBits(long n)
{
  return BITS ^ n;
}

int main()
{
  ofstream fout(getenv("OUTPUT_PATH"));

  string q_temp;
  getline(cin, q_temp);

  int q = stoi(ltrim(rtrim(q_temp)));

  for (int q_itr = 0; q_itr < q; q_itr++)
  {
    string n_temp;
    getline(cin, n_temp);

    long n = stol(ltrim(rtrim(n_temp)));

    long result = flippingBits(n);

    fout << result << "\n";
  }

  fout.close();

  return 0;
}

string ltrim(const string &str)
{
  string s(str);

  s.erase(
      s.begin(),
      find_if(s.begin(), s.end(), not1(ptr_fun<int, int>(isspace))));

  return s;
}

string rtrim(const string &str)
{
  string s(str);

  s.erase(
      find_if(s.rbegin(), s.rend(), not1(ptr_fun<int, int>(isspace))).base(),
      s.end());

  return s;
}