Submission #1108747

#	Time	Username	Problem	Language	Result	Execution time	Memory
1108747		Yang8on	Museum (CEOI17_museum)	C++17	100 / 100	563 ms	323400 KiB

museum

#include <bits/stdc++.h>
#define Y8o "Museum"
#define maxn (int) 1e4 + 5
#define ll long long
#define pii pair<int, int>
#define gb(i, j) ((i >> j) & 1)
#define all(x) x.begin(), x.end()
#define _left id * 2, l, mid
#define _right id * 2 + 1, mid + 1, r
#define fi(i, a, b) for(int i = a; i <= b; i ++)
#define fid(i, a, b) for(int i = a; i >= b; i --)

//#define f first
//#define s second

using namespace std;

mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
ll GetRandom(ll l, ll r) {
    return uniform_int_distribution<ll> (l, r) (rng);
}
void iof() {
    ios_base::sync_with_stdio(0);
    cin.tie(NULL), cout.tie(NULL);
    if(fopen(Y8o".inp", "r"))
    {
        freopen(Y8o".inp", "r", stdin);
//        freopen(Y8o".out", "w", stdout);
    }
}
void ctime() {
    cerr << "\n" << "\nTime elapsed: " << 1000 * clock() / CLOCKS_PER_SEC << "ms\n";
}

const ll INF = 1e18;

int n, k, st;
vector<pii> o[maxn];
int h[maxn];
vector<ll> dp[maxn][2];

vector<ll> cb(vector<ll> A, vector<ll> B, ll w) {
    vector<ll> ans (A.size() + B.size() - 1, INF);
    fi(i, 0, A.size() - 1) {
        fi(j, 0, B.size() - 1) {
            ans[i + j] = min(ans[i + j], A[i] + B[j] + (j > 0) * w);
        }
    }
    return ans;
}

vector<ll> minimum(vector<ll> A, vector<ll> B) {
    if(A.size() > B.size()) swap(A, B);
    while(A.size() < B.size()) A.push_back(INF);
    fi(i, 0, A.size() - 1) A[i] = min(A[i], B[i]);
    return A;
}

void dfs(int u, int p = 0) {
    dp[u][0] = { 0, 0 };
    dp[u][1] = { 0, -h[u] };

    for(auto [v, w] : o[u]) if(v != p) {
        h[v] = h[u] + w;
        dfs(v, u);
        vector<ll> tmp1 = cb(dp[u][0], dp[v][1], 2*w);
        vector<ll> tmp2 = cb(dp[u][1], dp[v][0], 2*w);

        dp[u][0] = cb(dp[u][0], dp[v][0], 2*w);
        dp[u][1] = minimum(tmp1, tmp2);
    }
}

void solve() {
    cin >> n >> k >> st;
    fi(i, 1, n - 1) {
        int u, v, w; cin >> u >> v >> w;
        o[u].push_back({ v, w }), o[v].push_back({ u, w });
    }

    dfs(st);
    cout << dp[st][1][k];
}


int main() {
    iof();

    int nTest = 1;
//    cin >> nTest;

    while(nTest --) {
        solve();
    }

    ctime();
    return 0;
}

Compilation message (stderr)

museum.cpp: In function 'std::vector<long long int> cb(std::vector<long long int>, std::vector<long long int>, long long int)':
museum.cpp:10:38: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   10 | #define fi(i, a, b) for(int i = a; i <= b; i ++)
......
   44 |     fi(i, 0, A.size() - 1) {
      |        ~~~~~~~~~~~~~~~~~~             
museum.cpp:44:5: note: in expansion of macro 'fi'
   44 |     fi(i, 0, A.size() - 1) {
      |     ^~
museum.cpp:10:38: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   10 | #define fi(i, a, b) for(int i = a; i <= b; i ++)
......
   45 |         fi(j, 0, B.size() - 1) {
      |            ~~~~~~~~~~~~~~~~~~         
museum.cpp:45:9: note: in expansion of macro 'fi'
   45 |         fi(j, 0, B.size() - 1) {
      |         ^~
museum.cpp: In function 'std::vector<long long int> minimum(std::vector<long long int>, std::vector<long long int>)':
museum.cpp:10:38: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   10 | #define fi(i, a, b) for(int i = a; i <= b; i ++)
......
   55 |     fi(i, 0, A.size() - 1) A[i] = min(A[i], B[i]);
      |        ~~~~~~~~~~~~~~~~~~             
museum.cpp:55:5: note: in expansion of macro 'fi'
   55 |     fi(i, 0, A.size() - 1) A[i] = min(A[i], B[i]);
      |     ^~
museum.cpp: In function 'void iof()':
museum.cpp:27:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   27 |         freopen(Y8o".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 20 / 20
• Subtask 2: 25 / 25
• Subtask 3: 35 / 35
• Subtask 4: 20 / 20