code-DP.cpp

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 * Code for the book "DAILY 43: Algorithmic Problems for Coding Interviews: Easy level, C++ edition"
 *
 * Licensed under the GNU General Public License, Version 3.0 (the "License");
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#include <iostream>
#include <vector>

class Solution {
public:
    std::vector<int> countBits(int n) {
        std::vector<int> answer(n + 1);
        answer[0] = 0;
        for (int i = 1; i <= n; ++i) {
            // Set_bits(N) = Set_bits(N>>1) + (1 if N is odd)
            answer[i] = answer[i / 2] + i % 2;
        }
        return answer;
    }
};

int main() {
    Solution sol;
    int n = 5;
    std::vector<int> result = sol.countBits(n);

    std::cout << "Number of set bits from 0 to " << n << " are:" << std::endl;
    for (int i = 0; i <= n; ++i) {
        std::cout << "Number " << i << " has " << result[i] << " set bits." << std::endl;
    }

    return 0;
}