Submission #478119

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
478119	2021-10-05T17:30:34 Z	bonopo	Dynamic Diameter (CEOI19_diameter)	C++17	7 / 100	5000 ms	66528 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;
    
        assert(last>0);
    }
}
 
// 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	9 ms	18764 KB	Output is correct
3	Correct	12 ms	18764 KB	Output is correct
4	Correct	25 ms	18812 KB	Output is correct
5	Correct	73 ms	19096 KB	Output is correct
6	Correct	9 ms	18636 KB	Output is correct
7	Correct	12 ms	18952 KB	Output is correct
8	Correct	11 ms	18892 KB	Output is correct
9	Correct	12 ms	18892 KB	Output is correct
10	Correct	33 ms	19020 KB	Output is correct
11	Correct	115 ms	19348 KB	Output is correct
12	Correct	22 ms	21068 KB	Output is correct
13	Correct	18 ms	21068 KB	Output is correct
14	Correct	21 ms	21124 KB	Output is correct
15	Correct	63 ms	21140 KB	Output is correct
16	Correct	183 ms	21572 KB	Output is correct
17	Correct	166 ms	65840 KB	Output is correct
18	Correct	173 ms	65900 KB	Output is correct
19	Correct	174 ms	65900 KB	Output is correct
20	Correct	272 ms	66000 KB	Output is correct
21	Correct	399 ms	66528 KB	Output is correct