oj.uz

Submission #428001

# Submission time Handle Problem Language Result Execution time Memory
428001 2021-06-15T07:00:47 Z juggernaut Capital City (JOI20_capital_city) C++17
1 / 100
 3000 ms 321512 KB 
#include<bits/stdc++.h>
#define fr first
#define sc second
using namespace std;
void usaco(string s){freopen((s+".in").c_str(),"r",stdin);freopen((s+".out").c_str(),"w",stdout);}
typedef long long ll;
#define USING_ORDERED_SET 0
#if USING_ORDERED_SET
#include<bits/extc++.h>
using namespace __gnu_pbds;
template<class T>using ordered_set=tree<T,null_type,less<T>,rb_tree_tag,tree_order_statistics_node_update>;
#endif
template<class T>void umax(T &a,T b){if(a<b)a=b;}
template<class T>void umin(T &a,T b){if(b<a)a=b;}
#ifdef IOI2021SG
    #define printl(args...)printf(args)
#else
    #define printl(args...)((void)0)
#endif
int n,k;
int tin[200005],tout[200005],timer,up[200005][18];
vector<int>g[200005],color[200005],g1[200005],g2[200005];
int a[200005];
void dfs(int v,int p){
    tin[v]=++timer;
    up[v][0]=p;
    for(int i=1;i<18;i++)up[v][i]=up[up[v][i-1]][i-1];
    for(int to:g[v])if(to!=p)dfs(to,v);
    tout[v]=++timer;
}
bool upper(int a,int b){
    return tin[a]<=tin[b]&&tout[a]>=tout[b];
}
int lca(int a,int b){
    if(upper(a,b))return a;
    if(upper(b,a))return b;
    for(int i=17;i>=0;i--)if(!upper(up[a][i],b))a=up[a][i];
    return up[a][0];
}
unordered_map<int,bool>vs[200005];
vector<pair<int,int>>edges;
void add_edge(int a,int b){
    if(a^b){
        if(vs[a][b])return;
        vs[a][b]=true;
        edges.emplace_back(a,b);
        g1[a].push_back(b);
        g2[b].push_back(a);
    }
}
void add(int v,int a,int b){
    int lca=::lca(a,b);
    while(a!=lca){
        a=up[a][0];
        add_edge(v,::a[a]);
    }
    while(b!=lca){
        b=up[b][0];
        add_edge(v,::a[b]);
    }
}
bool vis[200005];
vector<int>ordr,comp;
void dfs1(int v){
    vis[v]=true;
    for(int to:g1[v])if(!vis[to])dfs1(to);
    ordr.push_back(v);
}
void dfs2(int v){
    comp.push_back(v);
    vis[v]=true;
    for(int to:g2[v])if(!vis[to])dfs2(to);
}
int sz[200005];
int dp[200005];
int id[200005];
int go(int v){
    if(~dp[v])return dp[v];
    dp[v]=sz[v];
    for(int to:g[v])dp[v]+=go(to);
    return dp[v];
}
int main(){
    memset(dp,-1,sizeof dp);
    scanf("%d%d",&n,&k);
    for(int i=1;i<n;i++){
        int x,y;
        scanf("%d%d",&x,&y);
        g[x].push_back(y);
        g[y].push_back(x);
    }
    for(int i=1;i<=n;i++){
        scanf("%d",&a[i]);
        color[a[i]].push_back(i);
    }
    dfs(1,1);
    for(int i=1;i<=k;i++)
        for(int to1:color[i])
        for(int to2:color[i])if(to1>to2)add(i,to1,to2);
    for(int i=1;i<=k;i++)if(!vis[i])dfs1(i);
    memset(vis,0,sizeof vis);
    timer=0;
    for(int i=0;i<k;i++)if(!vis[ordr[k-i-1]]){
        comp.clear();
        dfs2(ordr[k-i-1]);
        timer++;
        sz[timer]=comp.size();
        for(int to:comp)id[to]=timer;
    }
    for(int i=1;i<=timer;i++)g[i].clear(),vis[i]=0;
    for(int i=1;i<=n;i++)vs[i].clear();
    for(auto to:edges)
        if(id[to.fr]!=id[to.sc]){
            if(vs[id[to.fr]][id[to.sc]])continue;
            vs[id[to.fr]][id[to.sc]]=1;
            g[id[to.fr]].push_back(id[to.sc]);
        }
    int ans=k;
    for(int i=1;i<=timer;i++)umin(ans,go(i));
    printf("%d",ans-1);
}

Compilation message

capital_city.cpp: In function 'void usaco(std::string)':
capital_city.cpp:5:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    5 | void usaco(string s){freopen((s+".in").c_str(),"r",stdin);freopen((s+".out").c_str(),"w",stdout);}
      |                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
capital_city.cpp:5:66: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    5 | void usaco(string s){freopen((s+".in").c_str(),"r",stdin);freopen((s+".out").c_str(),"w",stdout);}
      |                                                           ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
capital_city.cpp: In function 'int main()':
capital_city.cpp:85:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   85 |     scanf("%d%d",&n,&k);
      |     ~~~~~^~~~~~~~~~~~~~
capital_city.cpp:88:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   88 |         scanf("%d%d",&x,&y);
      |         ~~~~~^~~~~~~~~~~~~~
capital_city.cpp:93:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   93 |         scanf("%d",&a[i]);
      |         ~~~~~^~~~~~~~~~~~

Subtask #1
1.0 / 1.0

# Verdict Execution time Memory Grader output
1 Correct 20 ms 31052 KB Output is correct
2 Correct 21 ms 31064 KB Output is correct
3 Correct 19 ms 31068 KB Output is correct
4 Correct 20 ms 31072 KB Output is correct
5 Correct 19 ms 31012 KB Output is correct
6 Correct 19 ms 31004 KB Output is correct
7 Correct 19 ms 31052 KB Output is correct
8 Correct 19 ms 31052 KB Output is correct
9 Correct 18 ms 31052 KB Output is correct
10 Correct 18 ms 30972 KB Output is correct

Subtask #2
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 20 ms 31052 KB Output is correct
2 Correct 21 ms 31064 KB Output is correct
3 Correct 19 ms 31068 KB Output is correct
4 Correct 20 ms 31072 KB Output is correct
5 Correct 19 ms 31012 KB Output is correct
6 Correct 19 ms 31004 KB Output is correct
7 Correct 19 ms 31052 KB Output is correct
8 Correct 19 ms 31052 KB Output is correct
9 Correct 18 ms 31052 KB Output is correct
10 Correct 18 ms 30972 KB Output is correct
11 Correct 25 ms 31784 KB Output is correct
12 Correct 32 ms 31860 KB Output is correct
13 Correct 25 ms 31872 KB Output is correct
14 Correct 24 ms 31820 KB Output is correct
15 Incorrect 35 ms 32596 KB Output isn't correct
16 Halted 0 ms 0 KB -

Subtask #3
0 / 30.0

# Verdict Execution time Memory Grader output
1 Execution timed out 3075 ms 321512 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #4
0 / 59.0

# Verdict Execution time Memory Grader output
1 Correct 20 ms 31052 KB Output is correct
2 Correct 21 ms 31064 KB Output is correct
3 Correct 19 ms 31068 KB Output is correct
4 Correct 20 ms 31072 KB Output is correct
5 Correct 19 ms 31012 KB Output is correct
6 Correct 19 ms 31004 KB Output is correct
7 Correct 19 ms 31052 KB Output is correct
8 Correct 19 ms 31052 KB Output is correct
9 Correct 18 ms 31052 KB Output is correct
10 Correct 18 ms 30972 KB Output is correct
11 Correct 25 ms 31784 KB Output is correct
12 Correct 32 ms 31860 KB Output is correct
13 Correct 25 ms 31872 KB Output is correct
14 Correct 24 ms 31820 KB Output is correct
15 Incorrect 35 ms 32596 KB Output isn't correct
16 Halted 0 ms 0 KB -