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답안 #974412

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
974412 2024-05-03T09:57:06 Z marvinthang Star Trek (CEOI20_startrek) C++17
100 / 100
 56 ms 17352 KB 
/*************************************
*    author: marvinthang             *
*    created: 03.05.2024 16:12:22    *
*************************************/

#include <bits/stdc++.h>

using namespace std;

#define                  fi  first
#define                  se  second
#define                left  ___left
#define               right  ___right
#define                TIME  (1.0 * clock() / CLOCKS_PER_SEC)
#define             MASK(i)  (1LL << (i))
#define           BIT(x, i)  ((x) >> (i) & 1)
#define  __builtin_popcount  __builtin_popcountll
#define              ALL(v)  (v).begin(), (v).end()
#define           REP(i, n)  for (int i = 0, _n = (n); i < _n; ++i)
#define          REPD(i, n)  for (int i = (n); i-- > 0; )
#define        FOR(i, a, b)  for (int i = (a), _b = (b); i < _b; ++i) 
#define       FORD(i, b, a)  for (int i = (b), _a = (a); --i >= _a; ) 
#define       FORE(i, a, b)  for (int i = (a), _b = (b); i <= _b; ++i) 
#define      FORDE(i, b, a)  for (int i = (b), _a = (a); i >= _a; --i) 
#define        scan_op(...)  istream & operator >> (istream &in, __VA_ARGS__ &u)
#define       print_op(...)  ostream & operator << (ostream &out, const __VA_ARGS__ &u)
#ifdef LOCAL
    #include "debug.h"
#else
    #define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
    #define DB(...) 23
    #define db(...) 23
    #define debug(...) 23
#endif

template <class U, class V> scan_op(pair <U, V>)  { return in >> u.first >> u.second; }
template <class T> scan_op(vector <T>)  { for (size_t i = 0; i < u.size(); ++i) in >> u[i]; return in; }
template <class U, class V> print_op(pair <U, V>)  { return out << '(' << u.first << ", " << u.second << ')'; }
template <size_t i, class T> ostream & print_tuple_utils(ostream &out, const T &tup) { if constexpr(i == tuple_size<T>::value) return out << ")";  else return print_tuple_utils<i + 1, T>(out << (i ? ", " : "(") << get<i>(tup), tup); }
template <class ...U> print_op(tuple<U...>) { return print_tuple_utils<0, tuple<U...>>(out, u); }
template <class Con, class = decltype(begin(declval<Con>()))> typename enable_if <!is_same<Con, string>::value, ostream&>::type operator << (ostream &out, const Con &con) { out << '{'; for (__typeof(con.begin()) it = con.begin(); it != con.end(); ++it) out << (it == con.begin() ? "" : ", ") << *it; return out << '}'; }

const int MOD = 1e9 + 7;
namespace MODULAR {
    inline void fasterLLDivMod(unsigned long long x, unsigned y, unsigned &out_d, unsigned &out_m) {
        unsigned xh = (unsigned)(x >> 32), xl = (unsigned)x, d, m;
    #ifdef __GNUC__
        asm(
            "divl %4 \n\t"
            : "=a" (d), "=d" (m)
            : "d" (xh), "a" (xl), "r" (y)
        );
    #else
        __asm {
            mov edx, dword ptr[xh];
            mov eax, dword ptr[xl];
            div dword ptr[y];
            mov dword ptr[d], eax;
            mov dword ptr[m], edx;
        };
    #endif
        out_d = d; out_m = m;
    }
    template <class T> T invGeneral(T a, T b) {
        a %= b;
        if (!a) return b == 1 ? 0 : -1;
        T x = invGeneral(b, a);
        return x == -1 ? -1 : ((1 - 1LL * b * x) / a + b) % b;
    }
    template <int MOD> struct ModInt {
        unsigned int val;
        ModInt(void): val(0) {}
        ModInt(const long long &x) { *this = x; }
        ModInt & normalize(const unsigned int &v) {
            val = v >= MOD ? v - MOD : v;
            return *this;
        }
        bool operator ! (void) { return !val; }
        ModInt & operator = (const ModInt &x) { val = x.val; return *this; }
        ModInt & operator = (const long long &x) { return normalize(x % MOD + MOD); }
        ModInt operator - (void) { return ModInt(MOD - val); }
        ModInt & operator += (const ModInt &other) { return normalize(val + other.val); }
        ModInt & operator -= (const ModInt &other) { return normalize(val + MOD - other.val); }
        ModInt & operator /= (const ModInt &other) { return *this *= other.inv(); }
        ModInt & operator *= (const ModInt &other) {
            unsigned dummy;
            fasterLLDivMod((unsigned long long) val * other.val, MOD, dummy, val);
            return *this;
        }
        ModInt operator + (const ModInt &other) const { return ModInt(*this) += other; }
        ModInt operator - (const ModInt &other) const { return ModInt(*this) -= other; }
        ModInt operator * (const ModInt &other) const { return ModInt(*this) *= other; }
        ModInt operator / (const ModInt &other) const { return ModInt(*this) /= other; }
        ModInt pow(long long n) const {
            assert(n >= 0);
            ModInt res = 1, a = *this;
            for (; n; n >>= 1, a *= a) if (n & 1) res *= a;
            return res;
        }
        ModInt inv(void) const {
            int i = invGeneral((int) val, MOD);
            assert(~i);
            return i;
        }
        ModInt & operator ++ (void) { return *this += 1; }
        ModInt & operator -- (void) { return *this -= 1; }
        ModInt operator ++ (int) { ModInt old = *this; operator ++(); return old; }
        ModInt operator -- (int) { ModInt old = *this; operator --(); return old; }
        friend ModInt operator + (const long long &x, const ModInt &y) { return ModInt(x) + y; }
        friend ModInt operator - (const long long &x, const ModInt &y) { return ModInt(x) - y; }
        friend ModInt operator * (const long long &x, const ModInt &y) { return ModInt(x) * y; }
        friend ModInt operator / (const long long &x, const ModInt &y) { return ModInt(x) / y; }
        friend ostream & operator << (ostream &out, const ModInt &x) { return out << x.val; }
        friend istream & operator >> (istream &in, ModInt &x) { long long a; in >> a; x = a; return in; }
        explicit operator bool(void) const { return val; }
        explicit operator int(void) const { return val; }
    };  
    using Modular = ModInt <MOD>;
}
using namespace MODULAR;

template <class T> struct Matrix {
    int numRow, numCol; vector <T> val;
    // accessors
    typename vector<T>::iterator operator [] (int r) { return val.begin() + r * numCol; }
    inline T & at(int r, int c) { return val[r * numCol + c]; }
    inline T get(int r, int c) const { return val[r * numCol + c]; }
    // constructors
    Matrix() {}
    Matrix(int r, int c): numRow(r), numCol(c), val(r * c) {}
    Matrix(const vector <vector <T>> &d) {
        numRow = d.size();
        numCol = numRow ? d[0].size() : 0;
        for (int i = 0; i < numRow; ++i) {
            assert((int) d[i].size() == numCol);
            copy(d[i].begin(), d[i].end(), back_inserter(val));
        }
    }
    Matrix & set_value(T v) {
        for (int i = 0; i < numRow * numCol; ++i) val[i] = v;
        return *this;
    }
    // convert to 2D vector
    vector <vector <T>> vecvec(void) const {
        vector <vector <T>> res(numRow);
        for (int i = 0; i < numRow; ++i)
            copy(val.begin() + i * numCol, val.begin() + (i + 1) * numCol, back_inserter(res[i]));
        return res;
    }
    operator vector <vector <T>> () const { return vecvec(); }
    static Matrix identity(int n) {
        Matrix res(n, n);
        for (int i = 0; i < n; ++i) res.at(i, i) = T(1);
        return res;
    }
    friend istream & operator >> (istream &in, Matrix &res) {
        for (T &x: res.val) in >> x;
        return in;
    }
    friend ostream & operator << (ostream &out, const Matrix &res) {
        for (int i = 0; i < res.numRow * res.numCol; ++i)
            cout << res.val[i] << " \n"[i % res.numCol == res.numCol - 1];
        return out;
    }
    Matrix operator - (void) {
        Matrix res(numRow, numCol);
        for (int i = 0; i < numRow * numCol; ++i) res.val[i] = -val[i];
        return res;
    }
    Matrix operator * (const T &v) {
        Matrix res = *this;
        for (T &x: res.val) x *= v;
        return res;
    } 
    Matrix operator / (const T &v) {
        Matrix res = *this;
        const T inv = T(1) / v;
        for (T &x: res.val) x *= inv;
        return res;
    }
    Matrix operator + (const Matrix &other) const {
        int M = numRow, N = numCol;
        assert(M == other.numRow); assert(N == other.numCol);
        Matrix res = *this;
        for (int i = 0; i < numRow * numCol; ++i) res.val[i] += other.val[i];
        return res;
    }
    Matrix operator - (const Matrix &other) const {
        int M = numRow, N = numCol;
        assert(M == other.numRow); assert(N == other.numCol);
        Matrix res = *this;
        for (int i = 0; i < numRow * numCol; ++i) res.val[i] -= other.val[i];
        return res;
    }
    Matrix operator * (const Matrix &other) const {
        int M = numRow, N = numCol, P = other.numCol;
        assert(N == other.numRow);
        Matrix t_other = other.transpose();
        Matrix res(M, P);
        for (int i = 0; i < M; ++i)
            for (int j = 0; j < P; ++j)
                res.at(i, j) = inner_product(this->val.begin() + N * i, this->val.begin() + N * (i + 1), t_other.val.begin() + t_other.numCol * j, T(0));
        return res;
    }
    Matrix & operator *= (const T &v) { return *this = *this * v; }
    Matrix & operator /= (const T &v) { return *this = *this / v; }
    Matrix & operator += (const Matrix &other) { return *this = *this + other; }
    Matrix & operator -= (const Matrix &other) { return *this = *this - other; }
    Matrix & operator *= (const Matrix &other) { return *this = *this * other; }
    Matrix pow(long long Exp) const {
        int M = numRow;
        assert(M == numCol); assert(Exp >= 0);
        Matrix res = identity(M);
        if (!Exp) return res;
        bool is_id = true;
        for (int i = 63 - __builtin_clzll(Exp); i >= 0; --i) {
            if (!is_id) res *= res;
            if (Exp >> i & 1) res *= *this, is_id = false;
        }
        return res;
    }
    Matrix transpose(void) const {
        Matrix res(numCol, numRow);
        for (int i = 0; i < numRow; ++i)
            for (int j = 0; j < numCol; ++j)
                res.at(j, i) = this->get(i, j);
        return res;
    }
};

// end of template

void process(void) {
	int n; long long d; cin >> n >> d;
	vector <vector <int>> adj(n);
	REP(i, n - 1) {
		int u, v; cin >> u >> v; --u; --v;
		adj[u].push_back(v);
		adj[v].push_back(u);
	}
	vector <int> cnt_lose(n), cnt_fw(n), cnt_fl(n), f(n);
	auto cal = [&] (int u) {
		if (cnt_lose[u] == 1) f[u] = cnt_fl[u];
		else if (!cnt_lose[u]) f[u] = cnt_fw[u] + 1;
		else f[u] = 0;
	};
	auto dfs = [&] (auto &&dfs, int u, int par) -> void{
		for (int v: adj[u]) if (v != par) {
			dfs(dfs, v, u);
			cnt_lose[u] += !cnt_lose[v];
			(cnt_lose[v] ? cnt_fw[u] : cnt_fl[u]) += f[v];
		}
		cal(u);
	};
	dfs(dfs, 0, 0);
	vector <int> g(n);
	vector <int> lst_win, lst_lose;
	auto dfs2 = [&] (auto &&dfs, int u, int par) -> void {
		(cnt_lose[u] ? lst_win : lst_lose).push_back(u);
		g[u] = f[u];
		for (int v: adj[u]) if (v != par) {
			cnt_lose[u] -= !cnt_lose[v];
			(cnt_lose[v] ? cnt_fw[u] : cnt_fl[u]) -= f[v];
			cal(u);
			cnt_lose[v] += !cnt_lose[u];
			(cnt_lose[u] ? cnt_fw[v] : cnt_fl[v]) += f[u];
			cal(v);
			dfs(dfs, v, u);
			cnt_lose[v] -= !cnt_lose[u];
			(cnt_lose[u] ? cnt_fw[v] : cnt_fl[v]) -= f[u];
			cal(v);
			cnt_lose[u] += !cnt_lose[v];
			(cnt_lose[v] ? cnt_fw[u] : cnt_fl[u]) += f[v];
			cal(u);
		}
	};
	dfs2(dfs2, 0, 0);
	Modular k;
	for (int u: lst_win) k += g[u];
	for (int u: lst_lose) k -= g[u];
	Matrix <Modular> base({{lst_lose.size(), 1LL * n * n}});
	Matrix <Modular> trans({
		{k, 0},
		{lst_lose.size(), 1LL * n * n}
	});
	base *= trans.pow(d - 1);
	cout << (cnt_lose[0] ? base[0][1] - g[0] * base[0][0] : g[0] * base[0][0]) << '\n';
}

int main(void) {
	ios_base::sync_with_stdio(false); cin.tie(nullptr); // cout.tie(nullptr);
	file("startrek");
	// int t; cin >> t; while (t--)
	process();
	// cerr << "Time elapsed: " << TIME << " s.\n";
	return (0^0);
}

Compilation message

startrek.cpp: In function 'void process()':
startrek.cpp:281:39: warning: narrowing conversion of 'lst_lose.std::vector<int>::size()' from 'std::vector<int>::size_type' {aka 'long unsigned int'} to 'long long int' [-Wnarrowing]
  281 |  Matrix <Modular> base({{lst_lose.size(), 1LL * n * n}});
      |                          ~~~~~~~~~~~~~^~
startrek.cpp:284:17: warning: narrowing conversion of 'lst_lose.std::vector<int>::size()' from 'std::vector<int>::size_type' {aka 'long unsigned int'} to 'long long int' [-Wnarrowing]
  284 |   {lst_lose.size(), 1LL * n * n}
      |    ~~~~~~~~~~~~~^~
startrek.cpp: In function 'int main()':
startrek.cpp:30:61: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   30 |     #define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
      |                                                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
startrek.cpp:292:2: note: in expansion of macro 'file'
  292 |  file("startrek");
      |  ^~~~
startrek.cpp:30:94: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   30 |     #define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
      |                                                                                       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
startrek.cpp:292:2: note: in expansion of macro 'file'
  292 |  file("startrek");
      |  ^~~~

Subtask #1
0.0 / 0.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 1 ms 348 KB Output is correct

Subtask #2
7.0 / 7.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 344 KB Output is correct
5 Correct 0 ms 344 KB Output is correct

Subtask #3
8.0 / 8.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 0 ms 344 KB Output is correct
6 Correct 0 ms 348 KB Output is correct

Subtask #4
15.0 / 15.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 0 ms 344 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 1 ms 344 KB Output is correct
8 Correct 1 ms 604 KB Output is correct
9 Correct 1 ms 348 KB Output is correct
10 Correct 1 ms 348 KB Output is correct
11 Correct 1 ms 348 KB Output is correct

Subtask #5
15.0 / 15.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 0 ms 344 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 1 ms 344 KB Output is correct
8 Correct 1 ms 604 KB Output is correct
9 Correct 1 ms 348 KB Output is correct
10 Correct 1 ms 348 KB Output is correct
11 Correct 1 ms 348 KB Output is correct
12 Correct 40 ms 11744 KB Output is correct
13 Correct 45 ms 16228 KB Output is correct
14 Correct 37 ms 8652 KB Output is correct
15 Correct 56 ms 8456 KB Output is correct
16 Correct 46 ms 8472 KB Output is correct

Subtask #6
20.0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 0 ms 344 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 1 ms 344 KB Output is correct
8 Correct 1 ms 604 KB Output is correct
9 Correct 1 ms 348 KB Output is correct
10 Correct 1 ms 348 KB Output is correct
11 Correct 1 ms 348 KB Output is correct
12 Correct 1 ms 348 KB Output is correct
13 Correct 1 ms 344 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 0 ms 344 KB Output is correct
16 Correct 1 ms 348 KB Output is correct
17 Correct 1 ms 348 KB Output is correct
18 Correct 0 ms 344 KB Output is correct
19 Correct 1 ms 344 KB Output is correct
20 Correct 0 ms 348 KB Output is correct
21 Correct 1 ms 348 KB Output is correct
22 Correct 1 ms 604 KB Output is correct
23 Correct 1 ms 348 KB Output is correct
24 Correct 1 ms 348 KB Output is correct
25 Correct 1 ms 348 KB Output is correct
26 Correct 1 ms 348 KB Output is correct
27 Correct 1 ms 600 KB Output is correct
28 Correct 1 ms 344 KB Output is correct
29 Correct 1 ms 348 KB Output is correct
30 Correct 1 ms 600 KB Output is correct

Subtask #7
20.0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 0 ms 344 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 1 ms 344 KB Output is correct
8 Correct 1 ms 604 KB Output is correct
9 Correct 1 ms 348 KB Output is correct
10 Correct 1 ms 348 KB Output is correct
11 Correct 1 ms 348 KB Output is correct
12 Correct 40 ms 11744 KB Output is correct
13 Correct 45 ms 16228 KB Output is correct
14 Correct 37 ms 8652 KB Output is correct
15 Correct 56 ms 8456 KB Output is correct
16 Correct 46 ms 8472 KB Output is correct
17 Correct 1 ms 348 KB Output is correct
18 Correct 1 ms 344 KB Output is correct
19 Correct 0 ms 348 KB Output is correct
20 Correct 0 ms 344 KB Output is correct
21 Correct 1 ms 348 KB Output is correct
22 Correct 1 ms 348 KB Output is correct
23 Correct 0 ms 344 KB Output is correct
24 Correct 1 ms 344 KB Output is correct
25 Correct 0 ms 348 KB Output is correct
26 Correct 1 ms 348 KB Output is correct
27 Correct 1 ms 604 KB Output is correct
28 Correct 1 ms 348 KB Output is correct
29 Correct 1 ms 348 KB Output is correct
30 Correct 1 ms 348 KB Output is correct
31 Correct 1 ms 348 KB Output is correct
32 Correct 1 ms 600 KB Output is correct
33 Correct 1 ms 344 KB Output is correct
34 Correct 1 ms 348 KB Output is correct
35 Correct 1 ms 600 KB Output is correct
36 Correct 40 ms 11992 KB Output is correct
37 Correct 46 ms 16072 KB Output is correct
38 Correct 31 ms 8672 KB Output is correct
39 Correct 42 ms 8596 KB Output is correct
40 Correct 51 ms 8540 KB Output is correct
41 Correct 43 ms 14040 KB Output is correct
42 Correct 43 ms 14800 KB Output is correct
43 Correct 27 ms 7676 KB Output is correct
44 Correct 41 ms 8532 KB Output is correct
45 Correct 38 ms 8400 KB Output is correct

Subtask #8
15.0 / 15.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 1 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 344 KB Output is correct
7 Correct 0 ms 344 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 1 ms 348 KB Output is correct
12 Correct 0 ms 344 KB Output is correct
13 Correct 0 ms 348 KB Output is correct
14 Correct 1 ms 344 KB Output is correct
15 Correct 1 ms 604 KB Output is correct
16 Correct 1 ms 348 KB Output is correct
17 Correct 1 ms 348 KB Output is correct
18 Correct 1 ms 348 KB Output is correct
19 Correct 40 ms 11744 KB Output is correct
20 Correct 45 ms 16228 KB Output is correct
21 Correct 37 ms 8652 KB Output is correct
22 Correct 56 ms 8456 KB Output is correct
23 Correct 46 ms 8472 KB Output is correct
24 Correct 1 ms 348 KB Output is correct
25 Correct 1 ms 344 KB Output is correct
26 Correct 0 ms 348 KB Output is correct
27 Correct 0 ms 344 KB Output is correct
28 Correct 1 ms 348 KB Output is correct
29 Correct 1 ms 348 KB Output is correct
30 Correct 0 ms 344 KB Output is correct
31 Correct 1 ms 344 KB Output is correct
32 Correct 0 ms 348 KB Output is correct
33 Correct 1 ms 348 KB Output is correct
34 Correct 1 ms 604 KB Output is correct
35 Correct 1 ms 348 KB Output is correct
36 Correct 1 ms 348 KB Output is correct
37 Correct 1 ms 348 KB Output is correct
38 Correct 1 ms 348 KB Output is correct
39 Correct 1 ms 600 KB Output is correct
40 Correct 1 ms 344 KB Output is correct
41 Correct 1 ms 348 KB Output is correct
42 Correct 1 ms 600 KB Output is correct
43 Correct 40 ms 11992 KB Output is correct
44 Correct 46 ms 16072 KB Output is correct
45 Correct 31 ms 8672 KB Output is correct
46 Correct 42 ms 8596 KB Output is correct
47 Correct 51 ms 8540 KB Output is correct
48 Correct 43 ms 14040 KB Output is correct
49 Correct 43 ms 14800 KB Output is correct
50 Correct 27 ms 7676 KB Output is correct
51 Correct 41 ms 8532 KB Output is correct
52 Correct 38 ms 8400 KB Output is correct
53 Correct 45 ms 17352 KB Output is correct
54 Correct 47 ms 15560 KB Output is correct
55 Correct 24 ms 7812 KB Output is correct
56 Correct 39 ms 13260 KB Output is correct
57 Correct 36 ms 9720 KB Output is correct
58 Correct 42 ms 9624 KB Output is correct
59 Correct 36 ms 9700 KB Output is correct
60 Correct 36 ms 9712 KB Output is correct