2026

    1#include <bits/stdc++.h>
    2using namespace std;
    3typedef long long ll;
    4int main() {
    5    ios::sync_with_stdio(0); cin.tie(0); 
    6    int n; cin >> n;
    7    vector<int> cnt(n + 1);
    8    for (int i = 1; i <= floor(sqrt(n)); i++) {
    9        ll x2 = 1LL * i * i;
    10        int remain = n - x2;
    11        if (remain < 0) continue;
    12        int my = floor(sqrt(remain));
    13        if (my < i) continue;
    14        for (int j = i + 1; j <= my; j++) {
    15            ll y2 = 1LL * j * j;
    16            cnt[y2 + x2]++;
    17        }
    18    }
    19    vector<int> ans;
    20    for (int i = 1; i <= n; i++) {
    21        if (cnt[i] == 1) {
    22            ans.push_back(i);
    23        }
    24    }
    25    cout << ans.size() << '\n';
    26    for (int i = 0; i < ans.size(); i++) {
    27        cout << ans[i] << " \n"[i == ans.size() - 1];
    28    }
    29    return 0;
    30}
    31