Submission #478120

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
478120	2021-10-05T17:36:11 Z	bonopo	Dynamic Diameter (CEOI19_diameter)	C++17	7 / 100	5000 ms	66480 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);
    dfs(rt, 0);
 
    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);
        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	10 ms	18768 KB	Output is correct
2	Correct	9 ms	18764 KB	Output is correct
3	Correct	10 ms	18764 KB	Output is correct
4	Correct	18 ms	18764 KB	Output is correct
5	Correct	55 ms	19268 KB	Output is correct
6	Correct	10 ms	18652 KB	Output is correct
7	Correct	10 ms	18892 KB	Output is correct
8	Correct	11 ms	18892 KB	Output is correct
9	Correct	14 ms	19020 KB	Output is correct
10	Correct	26 ms	19044 KB	Output is correct
11	Correct	79 ms	19396 KB	Output is correct
12	Correct	15 ms	21068 KB	Output is correct
13	Correct	18 ms	21068 KB	Output is correct
14	Correct	21 ms	21052 KB	Output is correct
15	Correct	35 ms	21120 KB	Output is correct
16	Correct	108 ms	21580 KB	Output is correct
17	Correct	169 ms	65852 KB	Output is correct
18	Correct	176 ms	65892 KB	Output is correct
19	Correct	203 ms	65904 KB	Output is correct
20	Correct	208 ms	65980 KB	Output is correct
21	Correct	324 ms	66480 KB	Output is correct