Submission #995390

#	Time	Username	Problem	Language	Result	Execution time	Memory
995390		cpptowin	Synchronization (JOI13_synchronization)	C++17	100 / 100	250 ms	64584 KiB

synchronization

#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 (int)1e18
#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 ^ (1LL << j))
#define onbit(i, j) (i | (1LL << 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;
const int nsqrt = 450;
const int mod = 1e9 + 7;
int n,m,q;
vi ke[maxn];
struct BIT
{
    int t[maxn];
    void up(int x,int val)
    {
        for( ; x < maxn ; x += lb(x)) t[x] += val;
    }
    void up(int l,int r,int val)
    {
        up(l,val);
        up(r + 1,-val);
    }
    int get(int x)
    {
        int ans = 0;
        for( ; x ; x -= lb(x)) ans += t[x];
        return ans;
    }
}t;
int cnt,pos[maxn],tail[maxn],par[maxn][20];
void dfs(int u)
{
    pos[u] = ++cnt;
    for(int v : ke[u]) if(v != par[u][0])
    {
        par[v][0] = u;
        dfs(v);
    }
    tail[u] = cnt;
}
int find(int u)
{
    fod(i,19,0) if(t.get(pos[u]) == t.get(pos[par[u][i]])) u = par[u][i];
    return u;
}
int save[maxn];
bool on[maxn];
pii edge[maxn];
int res[maxn];
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 >> m >> q;
    fo(i,1,n - 1)
    {
        int u,v;
        cin >> u >> v;
        ke[u].pb(v);
        ke[v].pb(u);
        edge[i] = {u,v};
    }
    dfs(1);
    fo(j,1,19) fo(i,1,n) par[i][j] = par[par[i][j - 1]][j - 1];
    fo(i,1,n) t.up(pos[i],tail[i],1);
    fo(i,1,n) res[i] = 1;
    fo(i,1,m)
    {
        int id;
        cin >> id;
        auto [u,v] = edge[id];
        if(pos[u] > pos[v]) swap(u,v);
        u = find(u);
        if(!on[id])
        {
            res[u] = res[u] + res[v] - save[id];
            t.up(pos[v],tail[v],-1);
        }
        else
        {
            res[v] = save[id] = res[u];
            t.up(pos[v],tail[v],1);
        }
        on[id] = 1 - on[id];
    }
    fo(i,1,q)
    {
        int x;
        cin >> x;
        cout << res[find(x)];en;
    }
}

Compilation message (stderr)

synchronization.cpp:83:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   83 | main()
      | ^~~~
synchronization.cpp: In function 'int main()':
synchronization.cpp:88:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   88 |         freopen(name ".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
synchronization.cpp:89:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   89 |         freopen(name ".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 20 / 20
• Subtask 3: 10 / 10
• Subtask 4: 20 / 20
• Subtask 5: 40 / 40