Submission #922508

#	Time	Username	Problem	Language	Result	Execution time	Memory
922508		cpptowin	Museum (CEOI17_museum)	C++17	100 / 100	558 ms	784612 KiB

museum

#include<bits/stdc++.h>
#define fo(i,d,c) for(int i=d;i<=c;i++)
#define fod(i,c,d) for(int i=c;i>=d;i--)
#define maxn 1000010
#define N 1010
#define fi first
#define se second
#define pb emplace_back
#define en cout<<"\n";
// #define int long long
#define inf 1000000000
#define pii pair<int,int>
#define vii vector<pii>
#define lb(x) x&-x
#define bit(i,j) ((i>>j)&1)
#define offbit(i,j) (i^(1<<j))
#define onbit(i,j) (i|(1<<j))
#define vi vector<int>
template <typename T1, typename T2> bool minimize(T1 &a, T2 b){if (a > b) {a = b; return true;} return false;}
template <typename T1, typename T2> bool maximize(T1 &a, T2 b){if (a < b) {a = b; return true;} return false;}
using namespace std;
int n,k,x;
vii ke[maxn];
int f[10010][10010][2];
int sz[maxn];
void dfs(int u,int parent)
{
    sz[u] = 1;
    for(auto [v,w] : ke[u])
    {
        if(v == parent) continue;
        dfs(v,u);
        sz[u] += sz[v];
        fod(i,sz[u],2) fo(j,max(0,i - sz[u] + sz[v]),min(i,sz[v])) 
        {
            f[u][i][0] = min(f[u][i][0],f[v][j][1] + f[u][i - j][0] + 2 * w);
            f[u][i][0] = min(f[u][i][0],f[v][j][0] + f[u][i - j][1] + w);
            f[u][i][1] = min(f[u][i][1],f[v][j][1] + f[u][i - j][1] + 2 * w);
        }
    }
}
main()
{
    #define name "TASK"
    if(fopen(name".inp","r"))
    {
       freopen(name".inp","r",stdin);
       freopen(name".out","w",stdout);
    }
    ios_base::sync_with_stdio(false);cin.tie(NULL);
    cin >> n >> k >> x;
    fo(i,1,n - 1)
    {
        int u,v,w;
        cin >> u >> v >> w;
        ke[u].pb(v,w);
        ke[v].pb(u,w);
    }
    fo(i,1,n) fo(j,2,k) f[i][j][0] = f[i][j][1] = inf;
    dfs(x,x);
    cout << f[x][k][0];
}

Compilation message (stderr)

museum.cpp:42:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   42 | main()
      | ^~~~
museum.cpp: In function 'int main()':
museum.cpp:47:15: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   47 |        freopen(name".inp","r",stdin);
      |        ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
museum.cpp:48:15: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   48 |        freopen(name".out","w",stdout);
      |        ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

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