Submission #478003

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
478003	2021-10-05T02:58:43 Z	bonopo	Dynamic Diameter (CEOI19_diameter)	C++17	7 / 100	5000 ms	76028 KB

diameter

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
using namespace std;
using namespace __gnu_pbds;
#define pb push_back
#define rc (i<<1)|1
#define lc (i<<1)
#define el "\n"
#define f first
#define s second

typedef long long ll;
const int MM=1e5+5, MOD=1e9+7, LOG=19;
int N, Q, W, sz[MM], bk[MM], pa[LOG][MM], in[LOG][MM], ot[LOG][MM], cp[LOG][MM], tp[LOG][MM], ct;
vector<int> adj[MM];
gp_hash_table<int,int> mp[MM];

struct node {
    ll lz;
    pair<ll,int> mx;
};

struct tree {
    vector<node> seg;
    int wt;

    void prop(int i, int l, int r) {
        if(l!=r) {
            seg[lc].lz+=seg[i].lz;
            seg[rc].lz+=seg[i].lz; }
        seg[i].mx.f+=seg[i].lz;
        seg[i].lz=0;
    }

    void build(int i, int sl, int sr) {
        if(sl==sr) {
            seg[i].mx={0,sl};
            return; }
        int m=sl+sr>>1;
        build(rc, m+1, sr);
        build(lc, sl, m);
        calc(i);
    }

    void calc(int i) {
        seg[i].mx=max(seg[lc].mx, seg[rc].mx);
    }

    void upd(int i, int sl, int sr, int l, int r, ll v) {
        if(l>sr || r<sl) return;
        if(l<=sl&&sr<=r) {
            seg[i].lz+=v;
            prop(i, sl, sr); return; }
        int m=sl+sr>>1;
        upd(rc, m+1, sr, l, r, v);
        upd(lc, sl, m, l, r, v);
        calc(i);
    }

    pair<ll,int> rmq(int i, int sl, int sr, int l, int r) {
        if(l>sr || r<sl) return {0,0};
        if(l<=sl&&sr<=r) return seg[i].mx;
        int m=sl+sr>>1;
        return max(rmq(lc, sl, m, l, r), rmq(rc, m+1, sr, l, r));
    }

    void init(int n) {
        wt=n;
        seg.resize(4*n+4);
        build(1, 1, n);
    }
} st[MM];

int crt(int u, int th, int fa) {
    for(int &v:adj[u]) if(v!=fa&&!bk[v]&&sz[v]>=th) {
        return crt(v, th, u); }
    return u;
}

void dfs(int u, int fa) {
    sz[u]=1;
    for(int &v:adj[u]) if(v!=fa&&!bk[v]) {
        dfs(v, u);
        sz[u]+=sz[v];
    }
}

void etr(int u, int fa, int lvl, int rt, int tv) {
    in[lvl][u]=++ct; cp[lvl][u]=rt; tp[lvl][u]=tv; mp[rt][ct]=u;
    for(int &v:adj[u]) if(v!=fa&&!bk[v]) {
        etr(v, u, lvl, rt, tv); }
    ot[lvl][u]=ct;
}

void rec(int rt, int nds, int fa=-1, int lvl=0) {
    dfs(rt, 0);

    // find centroid
  //  cout<<"centroid for "<<rt<<" nds "<<nds<<" lvl "<<lvl<<" is ";
    rt=crt(rt, nds/2, 0); pa[lvl][rt]=fa;
  //  cout<<rt<<el;

    bk[rt]=true; ct=0;

    // get ett
    cp[lvl][rt]=tp[lvl][rt]=rt;
    for(int &v:adj[rt]) if(!bk[v]) etr(v, rt, lvl, rt, v);

    // construct tree
    st[rt].init(nds);

    for(int &v:adj[rt]) if(!bk[v]) {
        rec(v, sz[v], rt, lvl+1);
    }
}

ll qry(int u, int v, ll val) {
    ll ret=0;

    // find smallest component
    int cur=0;
    while(cur<LOG-1&&cp[cur+1][u]!=0) ++cur;
  //  cout<<"iterating on "<<u<<" starting with "<<cur<<" delta "<<val<<el;

    // jump
    int crt=u;
    while(~cur) {
        // update edge
     //   cout<<"crt "<<crt<<el;

        if(cp[cur][u]==crt&&cp[cur][v]==crt) {
            int w=(in[cur][u]>in[cur][v]?u:v);

           // cout<<"level "<<cur<<" w "<<w<<" cent "<<crt<<" updating "<<in[cur][w]<<" "<<ot[cur][w]<<el;
            st[crt].upd(1, 1, st[crt].wt, in[cur][w], ot[cur][w], val);

            // query max
            auto x=st[crt].rmq(1, 1, st[crt].wt, 1, st[crt].wt);
            x.s=mp[crt][x.s];
           // cout<<"x value "<<x.f<<" "<<x.s<<" "<<tp[cur][x.s]<<" "<<in[cur][tp[cur][x.s]]<<" "<<ot[cur][tp[cur][x.s]]<<el;
            auto y=max(st[crt].rmq(1, 1, st[crt].wt, 1, in[cur][tp[cur][x.s]]-1), st[crt].rmq(1, 1, st[crt].wt, ot[cur][tp[cur][x.s]]+1, st[crt].wt));
            //cout<<"y value "<<y.f<<" "<<x.s<<el;

            ll cnd=x.f+y.f;
            ret=max(ret, cnd);
        }

        crt=pa[cur--][crt];
    }

    return ret;
}

int32_t main() {
    cin.tie(nullptr)->sync_with_stdio(false);
    cin>>N>>Q>>W;
    vector<pair<ll,pair<int,int>>> edg;
    memset(pa, -1, sizeof(pa));
    for(int i=1; i<N; ++i) {
        ll u, v, w; cin>>u>>v>>w;
        adj[u].pb(v); adj[v].pb(u);
        edg.pb({w,{u,v}});
    }

    // preprocess
    rec(1, N);
    for(auto &e:edg) qry(e.s.f, e.s.s, e.f);

    ll last=0, e, w;
    for(int q=1; q<=Q; ++q) {
        cin>>e>>w;
        e=(e+last)%(N-1);
        w=(w+last)%W;
      //  cout<<"actual qry "<<e<<" "<<w<<el;

        last=qry(edg[e].s.f, edg[e].s.s, w-edg[e].f);
        cout<<last<<el; edg[e].f=w;
    }
}

// MM

Compilation message

diameter.cpp: In member function 'void tree::build(int, int, int)':
diameter.cpp:39:17: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   39 |         int m=sl+sr>>1;
      |               ~~^~~
diameter.cpp: In member function 'void tree::upd(int, int, int, int, int, ll)':
diameter.cpp:54:17: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   54 |         int m=sl+sr>>1;
      |               ~~^~~
diameter.cpp: In member function 'std::pair<long long int, int> tree::rmq(int, int, int, int, int)':
diameter.cpp:63:17: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   63 |         int m=sl+sr>>1;
      |               ~~^~~

Subtask #1
0 / 11.0

#	Verdict	Execution time	Memory	Grader output
1	Incorrect	28 ms	34444 KB	Output isn't correct
2	Halted	0 ms	0 KB	-

Subtask #2
0 / 13.0

#	Verdict	Execution time	Memory	Grader output
1	Incorrect	28 ms	34444 KB	Output isn't correct
2	Halted	0 ms	0 KB	-

Subtask #3
7.0 / 7.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	25 ms	34404 KB	Output is correct
2	Correct	28 ms	34380 KB	Output is correct
3	Correct	25 ms	34356 KB	Output is correct
4	Correct	32 ms	34516 KB	Output is correct
5	Correct	73 ms	34768 KB	Output is correct
6	Correct	27 ms	34380 KB	Output is correct
7	Correct	28 ms	34600 KB	Output is correct
8	Correct	30 ms	34628 KB	Output is correct
9	Correct	28 ms	34636 KB	Output is correct
10	Correct	39 ms	34656 KB	Output is correct
11	Correct	92 ms	35064 KB	Output is correct
12	Correct	31 ms	36504 KB	Output is correct
13	Correct	31 ms	36472 KB	Output is correct
14	Correct	32 ms	36516 KB	Output is correct
15	Correct	49 ms	36596 KB	Output is correct
16	Correct	119 ms	36996 KB	Output is correct
17	Correct	129 ms	75448 KB	Output is correct
18	Correct	128 ms	75436 KB	Output is correct
19	Correct	132 ms	75468 KB	Output is correct
20	Correct	171 ms	75572 KB	Output is correct
21	Correct	248 ms	76028 KB	Output is correct