Submission #1119859

#	Time	Username	Problem	Language	Result	Execution time	Memory
1119859		btninh	Race (IOI11_race)	C++17	Compilation error	0 ms	0 KiB

race

#include <bits/stdc++.h>

#define int long long
#define N 100005
#define pb push_back
#define mod 1000000007
#define fi first
#define se second
#define all(x) x.begin(), x.end()
#define sz(x) (int)x.size()
#define pii pair<int,int>
#define INF 1e18
#define FOR(i, a, b) for(int i = a; i <= b; ++i)
#define FORD(i, a, b) for(int i = a; i >= b; --i)

using namespace std;

int n, k, sz[N], ans = INF;
bool vis[N];
map<int,int> cnt;
vector<pii> g[N];

int dfs(int u, int p = -1)
{
    sz[u] = 1;
    for(auto [v, w] : g[u])
    {
        if (v != p && !vis[v])
        {
            sz[u] += dfs(v, u);
        }
    }
    return sz[u];
}

int centroid(int u, int p, int len)
{
    for(auto [v, w] : g[u])
    {
        if (v != p && !vis[v] && sz[v] > len / 2)
            return centroid(v, u, len);
    }
    return u;
}

void calc(int u, int p, bool t, int sum, int d = 1)
{
    if (t == 0)
    {
        if (!cnt[sum])
            cnt[sum] = d;
        else
            cnt[sum] = min(cnt[sum], d);
    }
    else{
        if (cnt[k - sum])
            ans = min(ans, d + cnt[k - sum]);
    }
    for(auto [v, w] : g[u])
    {
        if (v != p && !vis[v])
        {
            calc(v, u, t, sum + w, d + 1);
        }
    }
}

void solve(int u)
{
    int c = centroid(u, -1, dfs(u));
    vis[c] = true;
    for(auto [v, w] : g[c])
    {
        if (!vis[v])
        {
            calc(v, c, 0, w);
            calc(v, c, 1, w);
        }
    }
    for(auto [v, w] : g[c])
    {
        if (!vis[v]) solve(v);
    }
}

void Proc()
{
    cin >> n >> k;
    vector<pii> E;
    FOR(i, 1, n - 1)
    {
        int u, v;
        cin >> u >> v;
        ++u; ++v;
        E.pb({u, v});
    }
    for(int i = 0; i < n - 1; ++i)
    {
        int l; cin >> l;
        int u = E[i].fi, v = E[i].se;
        g[u].pb({v, l});
        g[v].pb({u, l});
    }
    cnt[0] = 0;
    solve(1);
    cout << (ans != INF ? ans : -1);
}

int32_t main() {

    if(fopen("test.inp", "r"))
    {
        freopen("test.inp", "r", stdin);
        freopen("test.out", "w", stdout);
    }

    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int T; T = 1;
    //cin >> T;
    while (T--) Proc();
}

Compilation message (stderr)

race.cpp: In function 'int32_t main()':
race.cpp:113:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  113 |         freopen("test.inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
race.cpp:114:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  114 |         freopen("test.out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
/usr/bin/ld: /tmp/ccCmM2tF.o: in function `main':
race.cpp:(.text.startup+0x0): multiple definition of `main'; /tmp/cc1ihplE.o:grader.cpp:(.text.startup+0x0): first defined here
/usr/bin/ld: /tmp/cc1ihplE.o: in function `main':
grader.cpp:(.text.startup+0x28): undefined reference to `best_path(int, int, int (*) [2], int*)'
collect2: error: ld returned 1 exit status