Submission #477986

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
477986	2021-10-05T00:47:33 Z	bonopo	Dynamic Diameter (CEOI19_diameter)	C++17	7 / 100	5000 ms	70444 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);
    }

    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+1);
        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: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	26 ms	34376 KB	Output isn't correct
2	Halted	0 ms	0 KB	-

Subtask #2
0 / 13.0

#	Verdict	Execution time	Memory	Grader output
1	Incorrect	26 ms	34376 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	34384 KB	Output is correct
2	Correct	31 ms	34492 KB	Output is correct
3	Correct	27 ms	34368 KB	Output is correct
4	Correct	33 ms	34568 KB	Output is correct
5	Correct	69 ms	35532 KB	Output is correct
6	Correct	26 ms	34404 KB	Output is correct
7	Correct	28 ms	34512 KB	Output is correct
8	Correct	39 ms	34580 KB	Output is correct
9	Correct	40 ms	34552 KB	Output is correct
10	Correct	40 ms	34792 KB	Output is correct
11	Correct	86 ms	35876 KB	Output is correct
12	Correct	35 ms	36128 KB	Output is correct
13	Correct	44 ms	36096 KB	Output is correct
14	Correct	34 ms	36160 KB	Output is correct
15	Correct	53 ms	36364 KB	Output is correct
16	Correct	109 ms	37528 KB	Output is correct
17	Correct	168 ms	68788 KB	Output is correct
18	Correct	142 ms	68832 KB	Output is correct
19	Correct	131 ms	68840 KB	Output is correct
20	Correct	166 ms	69116 KB	Output is correct
21	Correct	318 ms	70444 KB	Output is correct