Submission #856406


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#include <bits/stdc++.h>
using namespace std;

long long f(long long b, long long n) {
	if (n < b) return n;
	return f(b, n / b) + n % b;
}

vector<long long> divisors(long long n) {
	vector<long long> res;
	for (long long i = 1; i * i <= n; i++) {
		if (n % i == 0) {
			res.push_back(i);
			if (i != n / i) res.push_back(n / i);
		}
	}
	sort(res.begin(), res.end());
	return res;
}

int main() {
	long long n, s;
	cin >> n >> s;

	for (int i = 2; i < 1e6; i++) {
		if (f(i, n) == s) {
			cout << i << endl;
			return 0;
		}
	}

	if (n == s) {
		cout << s + 1 << endl;
		return 0;
	}

	if (n - s < 0) {
		cout << -1 << endl;
		return 0;
	}

	long long mini = LLONG_MAX;

	for (long long d : divisors(n - s)) {
		long long b = (n - s) / d + 1;

		if (b > 1 && f(b, n) == s) {
			mini = min(mini, b);
		}
	}

	if (mini == LLONG_MAX) {
		cout << -1 << endl;
	} else {
		cout << mini << endl;
	}
}

Submission Info

Submission Time
Task D - Digit Sum
User pekempey
Language C++14 (GCC 5.4.1)
Score 500
Code Size 950 Byte
Status AC
Exec Time 36 ms
Memory 256 KB

Judge Result

Set Name Sample All
Score / Max Score 0 / 0 500 / 500
Status
AC × 5
AC × 47
Set Name Test Cases
Sample subtask1_87654_30.txt, subtask1_87654_138.txt, subtask1_87654_45678.txt, subtask1_31415926535_1.txt, subtask1_1_31415926535.txt
All subtask1_100000000000_1.txt, subtask1_100000000000_100000000000.txt, subtask1_100000000000_2.txt, subtask1_100000000000_3.txt, subtask1_100000000000_50000000000.txt, subtask1_100000000000_50000000001.txt, subtask1_100000000000_99999999999.txt, subtask1_16983563041_1.txt, subtask1_1_1.txt, subtask1_1_2.txt, subtask1_1_31415926535.txt, subtask1_239484768_194586924.txt, subtask1_2_1.txt, subtask1_2_2.txt, subtask1_31415926535_1.txt, subtask1_49234683534_2461734011.txt, subtask1_4_1.txt, subtask1_58640129658_232122496.txt, subtask1_68719476735_35.txt, subtask1_68719476735_36.txt, subtask1_68719476735_37.txt, subtask1_68719476736_1.txt, subtask1_68719476736_2.txt, subtask1_72850192441_16865701.txt, subtask1_79285169301_27.txt, subtask1_82914867733_1676425945.txt, subtask1_8594813796_75700.txt, subtask1_87654_12345.txt, subtask1_87654_138.txt, subtask1_87654_30.txt, subtask1_87654_4294967308.txt, subtask1_87654_45678.txt, subtask1_97822032312_49157112.txt, subtask1_98750604051_977728851.txt, subtask1_99999515529_1.txt, subtask1_99999515529_316226.txt, subtask1_99999515529_316227.txt, subtask1_99999515529_316228.txt, subtask1_99999515529_49999757765.txt, subtask1_99999515529_49999757766.txt, subtask1_99999515530_2.txt, subtask1_99999999977_1.txt, subtask1_99999999977_2.txt, subtask1_99999999977_49999999989.txt, subtask1_99999999977_49999999990.txt, subtask1_99999999999_1.txt, subtask1_99999999999_100000000000.txt
Case Name Status Exec Time Memory
subtask1_100000000000_1.txt AC 4 ms 256 KB
subtask1_100000000000_100000000000.txt AC 30 ms 256 KB
subtask1_100000000000_2.txt AC 35 ms 256 KB
subtask1_100000000000_3.txt AC 35 ms 256 KB
subtask1_100000000000_50000000000.txt AC 34 ms 256 KB
subtask1_100000000000_50000000001.txt AC 34 ms 256 KB
subtask1_100000000000_99999999999.txt AC 30 ms 256 KB
subtask1_16983563041_1.txt AC 4 ms 256 KB
subtask1_1_1.txt AC 4 ms 256 KB
subtask1_1_2.txt AC 6 ms 256 KB
subtask1_1_31415926535.txt AC 6 ms 256 KB
subtask1_239484768_194586924.txt AC 24 ms 256 KB
subtask1_2_1.txt AC 4 ms 256 KB
subtask1_2_2.txt AC 4 ms 256 KB
subtask1_31415926535_1.txt AC 30 ms 256 KB
subtask1_49234683534_2461734011.txt AC 32 ms 256 KB
subtask1_4_1.txt AC 4 ms 256 KB
subtask1_58640129658_232122496.txt AC 33 ms 256 KB
subtask1_68719476735_35.txt AC 9 ms 256 KB
subtask1_68719476735_36.txt AC 4 ms 256 KB
subtask1_68719476735_37.txt AC 33 ms 256 KB
subtask1_68719476736_1.txt AC 4 ms 256 KB
subtask1_68719476736_2.txt AC 4 ms 256 KB
subtask1_72850192441_16865701.txt AC 34 ms 256 KB
subtask1_79285169301_27.txt AC 4 ms 256 KB
subtask1_82914867733_1676425945.txt AC 34 ms 256 KB
subtask1_8594813796_75700.txt AC 6 ms 256 KB
subtask1_87654_12345.txt AC 4 ms 256 KB
subtask1_87654_138.txt AC 4 ms 256 KB
subtask1_87654_30.txt AC 4 ms 256 KB
subtask1_87654_4294967308.txt AC 7 ms 256 KB
subtask1_87654_45678.txt AC 7 ms 256 KB
subtask1_97822032312_49157112.txt AC 36 ms 256 KB
subtask1_98750604051_977728851.txt AC 36 ms 256 KB
subtask1_99999515529_1.txt AC 16 ms 256 KB
subtask1_99999515529_316226.txt AC 35 ms 256 KB
subtask1_99999515529_316227.txt AC 16 ms 256 KB
subtask1_99999515529_316228.txt AC 19 ms 256 KB
subtask1_99999515529_49999757765.txt AC 35 ms 256 KB
subtask1_99999515529_49999757766.txt AC 34 ms 256 KB
subtask1_99999515530_2.txt AC 16 ms 256 KB
subtask1_99999999977_1.txt AC 35 ms 256 KB
subtask1_99999999977_2.txt AC 35 ms 256 KB
subtask1_99999999977_49999999989.txt AC 34 ms 256 KB
subtask1_99999999977_49999999990.txt AC 34 ms 256 KB
subtask1_99999999999_1.txt AC 36 ms 256 KB
subtask1_99999999999_100000000000.txt AC 31 ms 256 KB