枚举所有 x ,可能的 y 最多只有三个,x 也很少因为是阶乘
#include <bits/stdc++.h>
using namespace std;
#define int long long
const int N = 2e5 + 5;
int __t = 1, n, y, fac = 2, ans, ansx = 1, ansy = 1;
void ck(int x, int y) {
if (y == 2 || y == 0)
return;
if (abs((fac - 1) * y - n) < ans) {
ans = abs((fac - 1) * y - n);
ansx = x;
ansy = y;
}
return;
}
void solve() {
cin >> n;
ans = n;
for (int x = 3; fac <= n; x++) {
fac *= x;
y = n / (fac - 1);
ck(x, y - 1);
ck(x, y);
ck(x, y + 1);
}
cout << ansx << ' ' << ansy << endl;
return;
}
int32_t main() {
#ifdef ONLINE_JUDGE
ios::sync_with_stdio(false);
cin.tie(0);
#endif
// cin >> __t;
while (__t--)
solve();
return 0;
}

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