Submission #478118

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
478118	2021-10-05T17:27:56 Z	bonopo	Dynamic Diameter (CEOI19_diameter)	C++17	7 / 100	5000 ms	66476 KB

diameter

#include "bits/stdc++.h"
using namespace std;
#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]; ll av[MM];
multiset<ll> ast;
unordered_map<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);
    }
}
 
void qry(int u, int v, ll val) {

    // 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);
            ast.erase(ast.find(av[crt]));
 
           // 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; av[crt]=cnd;
            ast.insert(av[crt]);
        }
 
        crt=pa[cur--][crt];
    }
 
}
 
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(int i=1; i<=N; ++i) ast.insert(0);
    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;
        qry(edg[e].s.f, edg[e].s.s, w-edg[e].f);
        qry(edg[e].s.s, edg[e].s.f, 0);
        last=*ast.rbegin(); edg[e].f=w;
        cout<<last<<el;
    }
}
 
// MM

Compilation message

diameter.cpp: In member function 'void tree::build(int, int, int)':
diameter.cpp:38:17: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   38 |         int m=sl+sr>>1;
      |               ~~^~~
diameter.cpp: In member function 'void tree::upd(int, int, int, int, int, ll)':
diameter.cpp:53:17: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   53 |         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:62:17: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   62 |         int m=sl+sr>>1;
      |               ~~^~~

Subtask #1
0 / 11.0

#	Verdict	Execution time	Memory	Grader output
1	Incorrect	9 ms	18764 KB	Output isn't correct
2	Halted	0 ms	0 KB	-

Subtask #2
0 / 13.0

#	Verdict	Execution time	Memory	Grader output
1	Incorrect	9 ms	18764 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	9 ms	18764 KB	Output is correct
2	Correct	10 ms	18764 KB	Output is correct
3	Correct	14 ms	18764 KB	Output is correct
4	Correct	22 ms	18848 KB	Output is correct
5	Correct	94 ms	19176 KB	Output is correct
6	Correct	10 ms	18748 KB	Output is correct
7	Correct	11 ms	18892 KB	Output is correct
8	Correct	12 ms	18892 KB	Output is correct
9	Correct	12 ms	18892 KB	Output is correct
10	Correct	33 ms	19028 KB	Output is correct
11	Correct	120 ms	19400 KB	Output is correct
12	Correct	16 ms	21068 KB	Output is correct
13	Correct	16 ms	21064 KB	Output is correct
14	Correct	19 ms	21080 KB	Output is correct
15	Correct	54 ms	21120 KB	Output is correct
16	Correct	164 ms	21588 KB	Output is correct
17	Correct	167 ms	65840 KB	Output is correct
18	Correct	175 ms	65856 KB	Output is correct
19	Correct	184 ms	65936 KB	Output is correct
20	Correct	216 ms	65968 KB	Output is correct
21	Correct	410 ms	66476 KB	Output is correct