Submission #279768

#	Time	Username	Problem	Language	Result	Execution time	Memory
279768		infinite_iq	Dynamic Diameter (CEOI19_diameter)	C++14	66 / 100	1329 ms	44508 KiB

diameter

#define fast ios_base::sync_with_stdio(0),cin.tie(0),cout.tie(0)
#include <bits/stdc++.h>
using namespace std;
#define sqr 340
#define mp make_pair
#define mid (l+r)/2
#define le node * 2 
#define ri node * 2 + 1 
#define pb push_back
#define ppb pop_back
#define fi first
#define se second
#define lb lower_bound
#define ub upper_bound
#define ins insert
#define era erase
#define C continue
#define mem(dp,i) memset(dp,i,sizeof(dp))
#define mset multiset
#define all(x) x.begin(), x.end()
#define gc getchar_unlocked
typedef long long ll;
typedef short int si;
typedef long double ld;
typedef pair<int,int> pi;
typedef pair<ll,ll> pll;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<pi> vpi;
typedef vector<pll> vpll;
typedef pair<double,ll>pdi;
const ll inf=1e18;
const ll Mod=1e9+7;
const ld Pi=acos(-1) ;
ll n , q , MX , Last ;
vpll v [100009] ;
pll edges [100009] ;
//
pair < pll , ll >  Query ( ll t ) {
        ll id , cost ;
        scanf ("%lld%lld",&id,&cost) ;
        id   = ( id   + Last ) % ( n - 1 ) ;
        cost = ( cost + Last ) % ( MX    ) ;
        ll a = edges [id] .fi , b = edges [id] .se ;
        if ( t ) {
                for ( auto &u : v [a] ) {
                        if ( u .fi == b ) {
                                u .se = cost ;
                                break ;
                        }
                }
                for ( auto &u : v [b] ) {
                        if ( u .fi == a ) {
                                u .se = cost ;
                                break ;
                        }
                }
        }
        return { { a , b } , cost } ;
}
void input () {
        cin >> n >> q >> MX ;
        for ( int i = 0 ; i < n - 1 ; i ++ ) {
                ll a , b , c ;
                scanf ("%lld%lld%lld", &a , &b , &c ) ;
                a -- , b -- ;
                edges [i] = { a , b } ;
                v [a] .pb ( { b , c } ) ;
                v [b] .pb ( { a , c } ) ;
        }
        if ( n == 2 ) {
                while ( q -- ) {
                        cout << Query ( 0 ) . se << endl ; ;
                }
                exit (0) ;
        }
}
// Sub1_2
pi Far ;
int Sub1_2 () {
        return ( n <= 5009 && q <= 5009 ) ;
}
void Dfs1 ( int node , int p , int Crnt ) {
        Far = max ( Far , { Crnt , node } ) ;
        for ( auto u : v [node] ) {
                if ( u .fi == p ) C ;
                Dfs1 ( u .fi , node , Crnt + u .se ) ;
        }
}
int BruteForce () {
        Far = { 0 , 0 } ;
        Dfs1 ( 0 , 0 , 0 ) ;
        Dfs1 ( Far .se , Far .se , 0 ) ;
        return Far .fi ;
}
void Sol1_2 () {
        while ( q -- ) {
                Query (1) ;
                Last = BruteForce () ;
                printf ("%lld\n",Last) ;
        }
        exit (0) ;
}
// Sub4 
ll Dp [100009] , Mx [100009] , P [100009] ;
int Sub4 () {
        for ( int i = 0 ; i < n - 1 ; i ++ ) {
                ll a = edges [i] .fi , b = edges [i] .se ;
                if ( a > b ) {
                        swap ( edges [i] .fi , edges [i] .se ) ;
                }
                a ++ , b ++ ;
                if ( a * 2 != b && a * 2 + 1 != b ) return 0 ;
        }
        return 1 ;
}
void Fill ( int node , int p ) {
        P [node] = p ;
        for ( auto u : v [node] ) {
                if ( u .fi == p ) C ;
                Fill ( u .fi , node ) ;
                Dp [node] = max ( Dp [node] , Dp [u.fi] ) ;
                Dp [node] = max ( Dp [node] , Mx [u.fi] + u .se + Mx [node] ) ;
                Mx [node] = max ( Mx [node] , Mx [u.fi] + u .se ) ;
        }
        Dp [node] = max ( Dp [node] , Mx [node] ) ;
}
void Up ( int node ) {
        Dp [node] = 0 , Mx [node] = 0 ;
        for ( auto u : v [node] ) {
                if ( u .fi == P [node] ) C ;
                Dp [node] = max ( Dp [node] , Dp [u.fi] ) ;
                Dp [node] = max ( Dp [node] , Mx [u.fi] + u .se + Mx [node] ) ;
                Mx [node] = max ( Mx [node] , Mx [u.fi] + u .se ) ;
        }
        if ( P [node] != node )
                Up ( P  [node] ) ;
}
void Sol4 () {
        Fill ( 0 , 0 ) ;
        while ( q -- ) {
                pair < pll , ll > Ret  = Query (1) ;
                ll a = Ret .fi.fi , b = Ret .fi.se , cost = Ret .se ;
                Up ( a ) ;
                Last =  Dp [0] ;
                printf ("%lld\n",Dp [0]);
        }
  		exit (0) ; 
}
// Sub3_5
mset < ll > s ;
map < pll , ll > Val ;
ll Ord [100009] , Col [100009] , st [100009] , en [100009] ;
ll tree [400009] , lzy [400009] ;
void lzyUpd ( int node , int l , int r ) {
        tree [node] += lzy [node] ;
        if ( l != r ) {
                lzy [le] += lzy [node] ;
                lzy [ri] += lzy [node] ;
        }
        lzy [node] = 0 ;
}
void upd ( int node , int l , int r , int s , int e , ll val ) {
        lzyUpd ( node , l , r ) ;
        if ( s > r || e < l ) return ;
        if ( s <= l && e >= r ) {
                lzy [node] = val ;
                lzyUpd ( node , l , r ) ;
                return ;
        }
        upd ( le , l , mid , s , e , val ) ;
        upd ( ri , mid +1 , r , s , e , val ) ;
        tree [node] = max ( tree [le] , tree [ri] ) ;
}
ll query ( int node , int l , int r , int s , int e ) {
        lzyUpd ( node , l , r ) ;
        if ( s > r || e < l ) return 0ll ;
        if ( s <= l && e >= r ) return tree [node] ;
        return max ( query ( le , l , mid , s , e ) , query ( ri , mid + 1 , r , s , e ) ) ;
}
int timer = 0 , CrntCol = 0 ;
void Dfs ( int node , int p , ll crnt ) {
        Ord [timer] = node ;
        upd ( 1 , 0 , n -1 , timer , timer , crnt ) ;
        Col [node] = CrntCol ;
        st  [node] = timer ++ ;
        P   [node] = p ;
        for ( auto u : v [node] ) {
                Val [ mp ( u.fi , node ) ] = u .se ;
                if ( u.fi == p ) C ;
                Dfs ( u .fi , node , crnt + u .se ) ;
                CrntCol += ( node == 0 ) ;
        }
        en [node] = timer - 1 ;
}
ll Ans () {
        ll sum = 0 ;
        auto it = -- s.end () ;
        sum += *it ;
        if ( it != s.begin () ) {
                it -- ;
                sum += *it ;
        }
        return sum ;
}
void Sol3_5 () {
        Dfs ( 0 , 0 , 0 ) ;
        for ( auto u : v [0] ) {
                int l = st [u.fi] , r = en [u.fi] ;
                Mx [ Col [u.fi] ] = query ( 1 , 0 , n-1 , l , r ) ;
                s .ins ( Mx [ Col [u.fi] ] ) ;
        }
        for ( int i = 0 ; i < n -1 ; i ++ ) {
                int a = edges [i] .fi , b = edges [i] .se ;
                if ( P [a] == b ) {
                        swap ( edges [i] .fi , edges [i] .se ) ;
                }
        }
        while ( q -- ) {
                pair < pll , ll > Ret = Query (0) ;
                ll a = Ret .fi.fi , b = Ret .fi.se , cost = Ret .se ;
                ll bon = cost - Val [ mp ( a , b ) ] ;
                Val [ mp ( a , b ) ] = cost ;
                ll l = st [b] , r = en [b] ;
                upd ( 1 , 0 , n-1 , l , r , bon ) ;
                ll NODE = v [0][Col[b]] .fi ;
                l = st [NODE] , r = en [NODE] ;
                s .era ( s .find ( Mx [ Col [b] ] ) ) ;
                Mx [ Col [b] ] = query ( 1 , 0 , n -1 , l , r ) ;
                s .ins ( Mx [ Col [b] ] ) ;
                Last = Ans () ;
                printf ("%lld\n",Last) ;
        }
}
int main () {
        input () ;
        if ( Sub1_2 () ) Sol1_2 () ; 
        if ( Sub4   () ) Sol4   () ;
        Sol3_5 () ;
}

Compilation message (stderr)

diameter.cpp: In function 'void Sol4()':
diameter.cpp:143:37: warning: unused variable 'b' [-Wunused-variable]
  143 |                 ll a = Ret .fi.fi , b = Ret .fi.se , cost = Ret .se ;
      |                                     ^
diameter.cpp:143:54: warning: unused variable 'cost' [-Wunused-variable]
  143 |                 ll a = Ret .fi.fi , b = Ret .fi.se , cost = Ret .se ;
      |                                                      ^~~~
diameter.cpp: In function 'std::pair<std::pair<long long int, long long int>, long long int> Query(ll)':
diameter.cpp:41:15: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   41 |         scanf ("%lld%lld",&id,&cost) ;
      |         ~~~~~~^~~~~~~~~~~~~~~~~~~~~~
diameter.cpp: In function 'void input()':
diameter.cpp:65:23: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   65 |                 scanf ("%lld%lld%lld", &a , &b , &c ) ;
      |                 ~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 11 / 11
• Subtask 2: 13 / 13
• Subtask 3: 0 / 7
• Subtask 4: 18 / 18
• Subtask 5: 24 / 24
• Subtask 6: 0 / 27