LeetCode Tasks

#include <iostream>
#include <string>

using std::string;

string addBinary(string a, string b) {
    const string& max = a.length() > b.length() ? a : b;
    const string& min = max == a ? b : a;
    char* result_buffer = new char[max.length() + 2];
    memset(result_buffer, 0, max.length() + 2);
    int insert_index = max.length();
    bool extra = false;
    for (int i = max.length() - 1, j = min.length() - 1; i >= 0; i--, j--)
    {
        int current = (max[i] - '0') + (j >= 0 ? min[j] - '0' : 0) + (extra ? 1 : 0);
        extra = current >= 2;
        current %= 2;
        result_buffer[insert_index--] = '0' + current;
    }
    char* res_pointer = result_buffer;
    if (extra)
    {
        res_pointer[insert_index] = '1';
    }
    else
    {
        res_pointer++;
    }
    string result(res_pointer);
    delete[] result_buffer;
    return result;
}

bool isPalindrome(int x)
{
    if (x < 0)
    {
        return false;
    }
    char buffer[11];
    memset(buffer, 0, 11);
    int insertIndex = 0;
    while (x > 0)
    {
        buffer[insertIndex++] = x % 10 + '0';
        x /= 10;
    }
    for (int i = 0, j = insertIndex - 1; i < j; i++, j--)
    {
        if (buffer[i] != buffer[j])
        {
            return false;
        }
    }
    return true;
}