Problem:
Score : 200 points

Problem Statement

Kurohashi has never participated in AtCoder Beginner Contest (ABC).

The next ABC to be held is ABC N (the N-th ABC ever held).
Kurohashi wants to make his debut in some ABC x such that all the digits of x in base ten are the same.

What is the earliest ABC where Kurohashi can make his debut?

Constraints

100 \leq N \leq 999

N is an integer.

Input

Input is given from Standard Input in the following format:

N

Output

If the earliest ABC where Kurohashi can make his debut is ABC n, print n.

Sample Input 1

111

Sample Output 1

111

The next ABC to be held is ABC 111, where Kurohashi can make his debut.

Sample Input 2

112

Sample Output 2

222

The next ABC to be held is ABC 112, which means Kurohashi can no longer participate in ABC 111.
Among the ABCs where Kurohashi can make his debut, the earliest one is ABC 222.

Sample Input 3

750

Sample Output 3

777

Solution in C++14 (GCC 5.4.1) (judge verdict: Accepted)

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

#define CPP_CAT(x,y) CPP_CAT_I(x,y)
#define CPP_CAT_I(x,y) x ## y
//#define CPP_STR(x) CPP_STR_I(x)
//#define CPP_STR_I(args...) #args
//#define ASSERT(expr...) assert((expr))

using i8 = int8_t;
using u8 = uint8_t;
using i16 = int16_t;
using u16 = uint16_t;
using i32 = int32_t;
using u32 = uint32_t;
using i64 = int64_t;
using u64 = uint64_t;
using f32 = float;
using f64 = double;
//using f80 = __float80;
#pragma endregion

#pragma region const
constexpr i64 INF = 1'010'000'000'000'000'017LL;
constexpr i64 MOD = 1'000'000'007LL;
constexpr f64 EPS = 1e-12;
constexpr f64 PI = 3.14159265358979323846;
#pragma endregion

#pragma region util
#define FOR(i, start, end) for(i64 i = (start), CPP_CAT(i,xxxx_end)=(end); i < CPP_CAT(i,xxxx_end); ++i)
#define REP(i, n) FOR(i, 0, n)
#define ALL(f,c,...) (([&](decltype((c)) cccc) { return (f)(std::begin(cccc), std::end(cccc), ## __VA_ARGS__); })(c))

template<typename C>
i64 SIZE(const C& c) { return static_cast<i64>(c.size()); }
template<typename T, size_t N>
i64 SIZE(const T(&)[N]) { return static_cast<i64>(N); }

template<typename T, typename U, typename Comp = less<>>
bool chmax(T& xmax, const U& x, Comp comp = {}) {
	if (comp(xmax, x)) {
		xmax = x;
		return true;
	}
	return false;
}
template<typename T, typename U, typename Comp = less<>>
bool chmin(T& xmin, const U& x, Comp comp = {}) {
	if (comp(x, xmin)) {
		xmin = x;
		return true;
	}
	return false;
}
#pragma endregion

#pragma region init
struct ProconInit {
	static constexpr int IOS_PREC = 15;
	static constexpr bool AUTOFLUSH = false;

	ProconInit() {
		cin.tie(nullptr);
		ios::sync_with_stdio(false);
		cout << fixed << setprecision(IOS_PREC);
		if (AUTOFLUSH)
			cout << unitbuf;
	}
} PROCON_INIT;
#pragma endregion

int main()
{
	i64 N;
	cin >> N;

	if (N % 111 == 0)
	{
		cout << N << endl;
	}
	else
	{
		cout << (N / 111 * 111 + 111) << endl;
	}
	return 0;
}