#include <iostream>
#include <string>
#include <regex>
#include <vector>
#include <algorithm>
 
using namespace std;
 
vector<string> NearestPalindromeNumbers(string &s)
{
    string x(s), y(s), z(s);
 
    int k = s.length();
    int j = k / 2;
    int i = k - j;
 
    if (regex_match(s, regex("^10+$"))) return {string(k - 1, '9'), (y[k - 1]++, y)};
 
    reverse_copy(&x[0], &x[j], &x[i]);
    if (x == s) return {x};
 
    bool ascending = x < s;
    char r = 1;
    if (ascending) {
        for_each(y.rend() - i, y.rend(), [&r](char &y) {if (r) if (r = ++y > '9') y = '0';});
    } else {
        for_each(y.rend() - i, y.rend(), [&r](char &y) {if (r) if (r = --y < '0') y = '9';});
    }
    reverse_copy(&y[0], &y[j], &y[i]);
 
    transform(x.rbegin(), x.rend(), y.rbegin(), z.rbegin(), [&r](char &x, char &y) {
        char z = x + y + r;
        return (r = z > '0' + '9') ? z -= 10 : z;
    });
    for (char &z : z) r = (z += 10 * r) % 2, z /= 2;
 
    string &a = ascending ? x : y, &b = ascending ? y : x;
 
    int d = strcmp(&s[0], &z[0]);
    if (!r && !d) return {a, b};
    return {d <= 0 ? a : b};
}
 
string q[] = {"0", "5", "17", "100", "2024", "12345679042654321", "31415926535897932384626433832795028841971693993751058209749445923078164062862089986280348253421170679821480865132823066470938446095505822317253594081284811174502841027019385211055596446229489549303819644288109756659334461284756482337867831652712019091456485669234603486104543266482133936072602491412737245870066063155881748815209209628292540917153643678925903600113305305488204665213841469519415116094330572703657595919530921861173819326117931051185480744623799627495673518857527248912279381830119491298336733624406566430860213949463952247371907021798609437027705392171762931767523846748184676694051320005681271452635608277857713427577896091736371787214684409012249534301465495853710507922796892589235420199561121290219608640344181598136297747713099605187072113499999983729780499510597317328160963185950244594553469083026425223082533446850352619311881710100031378387528865875332083814206171776691473035982534904287554687311595628638823537875937519577818577805321712268066130019278766111959092164201989"};
 
int main(void)
{
    for (auto &s : q) {
        auto v = NearestPalindromeNumbers(s);
        for (auto &x : v) cout << (&x == &v[0] ? "[" : ", ") << x;
        cout << "]" << endl;
    }
    return 0;
}

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