Submission #1227982

#	Time	Username	Problem	Language	Result	Execution time	Memory
1227982		thunopro	Rigged Roads (NOI19_riggedroads)	C++20	27 / 100	405 ms	82388 KiB

riggedroads

#include<bits/stdc++.h>
using namespace std ; 
#define maxn 300009
#define ll long long 
#define pb push_back 
#define fi first 
#define se second 
#define left id<<1
#define right id<<1|1 
#define re exit(0); 
#define _lower(x) lower_bound(v.begin(),v.end(),x)-v.begin()+1 
#define TIME ( 1.0*clock() / CLOCKS_PER_SEC )
#define CEIL(a,b) (a/b + (a%b!=0))
const int mod = 1e9+7 ;
const int INF = 1e9 ; 

typedef vector<int> vi ; 
typedef pair<int,int> pii ; 
typedef vector<pii> vii ; 

template < typename T > void chkmin ( T &a , T b ) { if ( a > b ) a = b ; } 
template < typename T > void chkmax ( T &a , T b ) { if ( a < b ) a = b ; } 

void add ( int &a , int b ) 
{
    a += b ; 
    if ( a >= mod ) a -= mod ; 
    if ( a < 0 ) a += mod ; 
}

void rf () 
{
#ifndef ONLINE_JUDGE
freopen("bai1.inp","r",stdin);
freopen ("bai1.out","w",stdout) ;
#endif
}

int _pow ( int a , int n ) 
{
    if ( n == 0 ) return 1 ; 
    int res = _pow (a,n/2) ; 
    if ( n % 2 ) return 1ll*res*res%mod*a%mod ; 
    else return 1ll*res*res%mod ; 
}

int n , m ; 
pii E [maxn] ; 
vi adjList [maxn] ; 
int root = 1 ; 

int answer [maxn] ; 
bool mst [maxn] ; 

int par [maxn][19] , dep [maxn] ; 
int sz [maxn] , bigChild [maxn] ; 
void dfs ( int u ) 
{
    sz [u] = 1 ; 
    bigChild [u] = -1 ; 
    for ( auto v : adjList [u] ) 
    {
        if ( v != par [u][0] ) 
        {
            dep [v] = dep [u] + 1 ; 
            par [v][0] = u ; 
            for ( int i = 1 ; i <= 18 ; i ++ ) par [v][i] = par[par[v][i-1]][i-1] ; 
            dfs (v) ; 
            sz [u] += sz [v] ; 
            if ( bigChild [u] == -1 || sz [v] > sz [bigChild[u]] ) bigChild [u] = v ; 
        }
    }
}
int lca ( int u , int v ) 
{
    if ( dep [u] < dep [v] ) swap (u,v) ; 
    int h = dep [u] - dep [v] ; 
    for ( int i = 18 ; i >= 0 ; i -- ) if ( h >> i & 1 ) u = par [u][i] ; 
    if ( u == v ) return u ; 
    for ( int i = 18 ; i >= 0 ; i -- ) if ( par [u][i] != par [v][i] ) u = par [u][i] , v = par [v][i] ; 
    return par [u][0] ; 
}
int distance ( int u , int v ) 
{
    return dep [u] + dep [v] - 2*dep[lca(u,v)] ; 
}

int head [maxn] , num_head = 1 , pos [maxn] , Id [maxn] ; 
void hld ( int u ) 
{
    static int cnt = 0 ; 
    if ( head [num_head] == 0 ) head [num_head] = u ; 
    Id [u] = num_head ; 
    pos [u] = ++ cnt ; 
    if ( bigChild [u] != -1 ) hld (bigChild [u]) ; 
    for ( auto v : adjList [u] ) 
    {
        if ( v != par [u][0] && v != bigChild [u] ) num_head ++ , hld (v) ; 
    }
}

struct shape {
    int fill , Min , lazy , flag ;
} T [maxn*4] ; 

void down ( int id , int l , int r , int mid ) 
{
    chkmin (T[left].Min,T[id].lazy) ; 
    chkmin (T[right].Min,T[id].lazy) ;
    chkmin (T[left].lazy,T[id].lazy) ; 
    chkmin (T[right].lazy,T[id].lazy) ;
    if ( T [id].flag ) 
    {
        T [left].fill = mid-l+1 ; 
        T [right].fill = r-mid ; 
        T [left].flag = true , T [right].flag = true ; 
    }
    T [id].flag = false ; 
    T [id].lazy = INF ; 
}
void update ( int id , int l , int r , int u , int v , int w ) 
{
    if ( l > v || r < u ) return ; 
    if ( u <= l && r <= v ) 
    {
        chkmin (T[id].Min,w) ; 
        chkmin (T[id].lazy,w) ; 
        T [id].fill = r-l+1 ; 
        T [id].flag = 1 ; 
        return ; 
    }
    int mid = (l+r)/2 ; 
    down (id,l,r,mid) ; 
    update (left,l,mid,u,v,w) ; 
    update (right,mid+1,r,u,v,w) ; 
    T [id].Min = min ( T[left].Min,T[right].Min) ; 
    T [id].fill = T [left].fill + T [right].fill ; 
}


int get_min ( int id , int l , int r , int pos ) 
{
    if ( l > pos || r < pos ) return INF ; 
    if ( l == r ) return T [id].Min ; 
    int mid = (l+r)/2 ; 
    down (id,l,r,mid) ; 
    return min(get_min(left,l,mid,pos),get_min(right,mid+1,r,pos)) ; 
}
void update ( int u , int v , int w ) 
{
    vi all_value = {u,v} ; 
    int Lca = lca (u,v) ; 
    for ( auto x : all_value ) 
    {
        while ( head [Id[x]] != head [Id[Lca]] ) 
        {
            update (1,1,n,pos[x],pos[head[Id[x]]],w) ; 
            x = par [head[Id[x]]][0] ; 
        }
        if ( x != Lca ) update (1,1,n,pos[Lca]+1,pos[x],w) ; 
    }
}

int get_fill ( int id , int l , int r , int u , int v ) 
{
    if ( l > v || r < u ) return 0 ; 
    if ( u <= l && r <= v ) return T [id].fill ;
    int mid = (l+r)/2 ; 
    down (id,l,r,mid) ;  
    return get_fill (left,l,mid,u,v) + get_fill (right,mid+1,r,u,v) ; 
}
int get_fill ( int u , int v ) 
{
    int sum = 0 ; 
    vi all_value = {u,v} ; 
    int Lca = lca (u,v) ; 
    for ( auto x : all_value ) 
    {
        while ( head [Id[x]] != head [Id[Lca]] ) 
        {
            sum += get_fill (1,1,n,pos[x],pos[head[Id[x]]]) ; 
            x = par [head[Id[x]]][0] ; 
        }
        if ( x != Lca ) sum += get_fill (1,1,n,pos[Lca]+1,pos[x]) ; 
    }
    return sum ; 
}
int main () 
{
    ios_base::sync_with_stdio(0); 
    cin.tie(0);cout.tie(0); 
    // rf () ;
    cin >> n >> m ; 
    for ( int i = 1 ; i <= m ; i ++ ) 
    {
        int u , v ; cin >> u >> v ; 
        E [i] = {u,v} ; 
    }

    for ( int i = 1 ; i < n ; i ++ ) 
    {
        int x ; cin >> x ; 
        mst [x] = true ; 
        int u  = E [x].fi , v = E[x].se ; 
        adjList [u] . pb (v) ; 
        adjList [v] . pb (u) ; 
    }

    dfs (1) ; 
    hld (1) ; 

    int current = 0 ; 

    set <int> remain_value ; 
    for ( int i = 1 ; i <= m ; i ++ ) remain_value . insert (i) ; 

    for ( int i = 1 ; i <= n*4 ; i ++ ) T [i].Min = T [i].lazy = INF ; 
    for ( int i = 1 ; i <= m ; i ++ ) 
    {
        int u = E[i].fi , v = E [i].se ; 
        if ( dep [u] > dep [v] ) swap (u,v) ; 
        if ( mst [i] == false ) 
        {
            answer [i] = current + distance (u,v) - get_fill (u,v) + 1 ; 
            update (u,v,current+1) ; 
        }
        else 
        {
            if ( get_min (1,1,n,pos[v] ) >= INF ) answer [i] = current + 1 , update (1,1,n,pos[v],pos[v],INF); 
            else answer [i] = *remain_value.lower_bound((get_min(1,1,n,pos[v]))) ; 
        }
        chkmax (current,answer[i]) ; 
        remain_value.erase(answer[i]) ; 

    }

    for ( int i = 1 ; i <= m ; i ++ ) cout << answer [i] << " " ; 
    return 0;
}

Compilation message (stderr)

riggedroads.cpp: In function 'void rf()':
riggedroads.cpp:34:8: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   34 | freopen("bai1.inp","r",stdin);
      | ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
riggedroads.cpp:35:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   35 | freopen ("bai1.out","w",stdout) ;
      | ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 8 / 8
• Subtask 2: 0 / 19
• Subtask 3: 9 / 9
• Subtask 4: 10 / 10
• Subtask 5: 0 / 10
• Subtask 6: 0 / 12
• Subtask 7: 0 / 32