diff --git a/day 24/day_24_max_n.cpp b/day 24/day_24_max_n.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..bbedcd30eb19ce12c10ef69e46e12c2af3a232b9
--- /dev/null
+++ b/day 24/day_24_max_n.cpp
@@ -0,0 +1,297 @@
+#include <bits/stdc++.h>
+
+#ifdef LOCAL
+#include "./cpp-dump/cpp-dump.hpp"
+#define pr(x) cpp_dump(x)
+#endif
+
+using namespace std;
+
+#define Mod(x,y) (((x)%(y)+(y))%(y))
+#define rep(i, a, b) for(ll (i) = (a); (i) < (b); ++(i))
+#define all(x) begin(x), end(x)
+#define pb push_back
+#define gcd __gcd
+#define sz(x) (ll)(x.size())
+
+typedef long long ll;
+typedef unsigned long long ull;
+typedef pair<ll, ll> pii;
+typedef vector<ll> vi;
+typedef vector<pii> vii;
+
+const bool debug = false;
+ll binaryToDecimal(string n) {
+ string num = n;
+ ll dec_value = 0;
+
+ // Initializing base value to 1, i.e 2^0
+ ll base = 1;
+
+ ll len = num.length();
+ for (int i = len - 1; i >= 0; i--) {
+ if (num[i] == '1')
+ dec_value += base;
+ base = base * 2;
+ }
+
+ return dec_value;
+}
+string decToBinary(ll n){// Size of an integer is assumed to be 32 bits
+ string res;
+ for (int i = 45; i >= 0; i--) {
+ ll k = n >> i;
+ if (k & 1)
+ res.pb('1');
+ else
+ res.pb('0');
+ }
+ return res;
+}
+string adding_a_zero_to_string(int i) {
+ string s = to_string(i);
+ if (s.size() == 1) s = "0" + s;
+ return s;
+}
+
+map<string, int> mp;
+
+map<pair<string, string>, string> ANDS, ORS, XORS;
+map<pair<string, string>, set<pair<char, string>>> OPS;
+map<string, pair<string, string>> ANDS_rev, ORS_rev, XORS_rev;
+
+void OPS_to() {
+ ANDS.clear();
+ ORS.clear();
+ XORS.clear();
+ ANDS_rev.clear();
+ ORS_rev.clear();
+ XORS_rev.clear();
+ for (auto p : OPS) {
+ string s1 = p.first.first, s2 = p.first.second;
+ for (auto q : p.second) {
+ if (q.first == '&') {
+ ANDS[{s1, s2}] = q.second, ANDS[{s2, s1}] = q.second;
+ ANDS_rev[q.second] = p.first;
+ }
+ if (q.first == '|') {
+ ORS[{s1, s2}] = q.second, ORS[{s2, s1}] = q.second;
+ ORS_rev[q.second] = p.first;
+ }
+ if (q.first == '^') {
+ XORS[{s1, s2}] = q.second, XORS[{s2, s1}] = q.second;
+ XORS_rev[q.second] = p.first;
+ }
+ }
+ }
+}
+
+int rec(string s) {
+ if (mp.count(s)) return mp[s];
+ int res = 0;
+
+ if (ANDS_rev.count(s)) {
+ auto p = ANDS_rev[s];
+ res = rec(p.first) & rec(p.second);
+ } else if (ORS_rev.count(s)) {
+ auto p = ORS_rev[s];
+ res = rec(p.first) | rec(p.second);
+ } else if (XORS_rev.count(s)) {
+ auto p = XORS_rev[s];
+ res = rec(p.first) ^ rec(p.second);
+ } else {
+ assert(false);
+ }
+ return (mp[s] = res);
+}
+
+void load_values(string sx, string sy) {
+ if (sz(sx) > 0) mp.clear();
+ for (int i = 45; i >= 0; i--) {
+ string s = to_string(i);
+ if (s.size() == 1) s = "0" + s;
+ if (sz(sx) > 0) {
+ mp["x"+s] = sx[45-i]-'0';
+ mp["y"+s] = sy[45-i]-'0';
+ }
+ }
+
+}
+
+ll get_z(string sx, string sy) {
+ vector<pair<string, int>> vs;
+ for (int i = 45; i >= 0; i--) {
+ string s = "z"+adding_a_zero_to_string(i);
+ vs.pb(make_pair(s, rec(s)));
+ }
+
+ sort(all(vs));
+ string bts = "";
+ for (auto p : vs) {
+ bts.pb(p.second+'0');
+ }
+ reverse(all(bts));
+ ll ans1 = binaryToDecimal(bts);
+ return ans1;
+}
+
+pair<string, string> rands() {
+ string sx, sy;
+ for (int i = 45; i >= 0; i--) {
+ int x1 = rand()%2;
+ int y1 = rand()%2;
+ sx += x1+'0';
+ sy += y1+'0';
+ }
+ return {sx, sy};
+}
+
+bool do_some() {
+ rep(i, 0, 5) {
+ vector<int> diff;
+ pair<string, string> randoms = rands();
+ string sx = randoms.first, sy = randoms.second;
+
+ load_values(sx, sy);
+
+ ll x = binaryToDecimal(sx), y = binaryToDecimal(sy);
+ ll z = get_z(sx, sy);
+ string sz1 = decToBinary(z);
+
+ ll z2 = x+y;
+ string sz2 = decToBinary(z2);
+
+ for (int i = 45; i >= 0; i--) if (sz1[45-i] != sz2[45-i]) {
+ diff.pb(i);
+ }
+
+ pr(sz1);
+ pr(sz2);
+ pr(diff);
+ pr(" ");
+ }
+
+ return true;
+}
+
+
+map<pair<pair<string, string>, char>, set<int>> associations;
+
+void get_associations(string s, int i) {
+ char c;
+ pair<string, string> p;
+ if (ANDS_rev.count(s)) {
+ p = ANDS_rev[s];
+ c = '&';
+ } else if (ORS_rev.count(s)) {
+ p = ORS_rev[s];
+ c = '|';
+ } else if (XORS_rev.count(s)) {
+ p = XORS_rev[s];
+ c = '^';
+ } else {
+ return;
+ assert(false);
+ }
+ associations[make_pair(make_pair(p.first, p.second), c)].insert(i);
+ get_associations(p.first, i);
+ get_associations(p.second, i);
+}
+
+void print_those_associatied(int j) {
+ associations.clear();
+ for (int i = 45; i >= 0; i--) {
+ string s = "z"+adding_a_zero_to_string(i);
+ get_associations(s, i);
+ }
+
+ pr("printing unique associations");
+ pr(j);
+ for (auto p : associations) {
+ if (p.second.count(j)) {
+ bool ok = true;
+ for (int k = 0; k < j; k++) if (p.second.count(k)) ok = false;
+ if (ok) {
+ if (p.first.second == '&') pr(make_pair(p.first, ANDS[p.first.first]));
+ if (p.first.second == '|') pr(make_pair(p.first, ORS[p.first.first]));
+ if (p.first.second == '^') pr(make_pair(p.first, XORS[p.first.first]));
+ }
+ }
+ }
+}
+
+void switch_some_pairs(string s1, string s2, char c1, string t1, string u1, string u2, char c2, string t2) {
+ pr("switching");
+ bool ok = (OPS[{s1, s2}].count(make_pair(c1, t1)) == 1);
+ assert(ok);
+ ok = (OPS[{u1, u2}].count(make_pair(c2, t2)) == 1);
+ assert(ok);
+
+ OPS[{s1, s2}].erase(make_pair(c1, t1));
+ OPS[{s2, s1}].erase(make_pair(c1, t1));
+
+ OPS[{u1, u2}].erase(make_pair(c2, t2));
+ OPS[{u2, u1}].erase(make_pair(c2, t2));
+
+ OPS[{s1, s2}].insert(make_pair(c1, t2));
+ OPS[{s2, s1}].insert(make_pair(c1, t2));
+ OPS[{u1, u2}].insert(make_pair(c2, t1));
+ OPS[{u2, u1}].insert(make_pair(c2, t1));
+
+ OPS_to();
+}
+
+//
+
+void solve() {
+ string s1, s2, t;
+ string op;
+ int bt;
+ while(cin >> s1 >> bt) {
+ mp[s1] = bt;
+ cin.ignore();
+ if (cin.peek() == '\n') break;
+ }
+ while(cin >> s1 >> op >> s2 >> t) {
+ if (op == "AND") {
+ OPS[{s1, s2}].insert(make_pair('&', t));
+ OPS[{s2, s1}].insert(make_pair('&', t));
+ } else if (op == "OR") {
+ OPS[{s1, s2}].insert(make_pair('|', t));
+ OPS[{s2, s1}].insert(make_pair('|', t));
+ } else if (op == "XOR") {
+ OPS[{s1, s2}].insert(make_pair('^', t));
+ OPS[{s2, s1}].insert(make_pair('^', t));
+ } else assert(false);
+ }
+
+ OPS_to();
+ rep(j, 0, 46) print_those_associatied(j);
+ do_some();
+ switch_some_pairs("x09", "y09", '&', "cnk", "x09", "y09", '^', "qwf");
+ switch_some_pairs("rkm", "ndq", '^', "vhm", "x14", "y14", '&', "z14");
+ switch_some_pairs("kqw", "kqj", '^', "mps", "snv", "jgq", '|', "z27");
+ switch_some_pairs("trn", "gpm", '^', "msq", "trn", "gpm", '&', "z39");
+ rep(j, 0, 46) print_those_associatied(j);
+ do_some();
+
+ set<string> ans = {"cnk", "vhm", "mps", "msq", "qwf", "z14", "z27", "z39"};
+ for (string s : ans) {
+ cout << s << ',';
+ }
+
+}
+
+// 6457374031397
+
+
+int main() {
+ ios::sync_with_stdio(0);cin.tie(0);
+ cout << setprecision(15) << fixed;
+
+#ifdef LOCAL
+ freopen("input.txt", "r", stdin);
+#endif
+
+ solve();
+}