Submission #1054712

# Submission time Handle Problem Language Result Execution time Memory
1054712 2024-08-12T11:42:06 Z alexander707070 Swapping Cities (APIO20_swap) C++14
0 / 100
157 ms 47800 KB
#include<bits/stdc++.h>
#include "swap.h"

#define MAXN 100007
using namespace std;

const int inf=1e9+7;

int n,m,a[MAXN],b[MAXN],c[MAXN],dep[MAXN];
vector< pair<int,int> > tree[MAXN];
vector<int> v[MAXN];
int parent[MAXN],res[MAXN];

struct info{
    int par,mins,maxe;
};

struct edge{
    int from,to,cost;

    inline friend bool operator < (edge fr,edge sc){
        return fr.cost<sc.cost;
    }
}e[MAXN];

struct unionfind{
    int dsu[MAXN],sz[MAXN];

    void init(){
        for(int i=1;i<=n;i++){
            dsu[i]=i; sz[i]=1;
        }
    }

    int root(int x){
        if(dsu[x]==x)return dsu[x];
        return root(dsu[x]);
    }

    void mergev(int x,int y){
        int rootx=root(x);
        int rooty=root(y);

        if(rootx==rooty)return;
        if(sz[rootx]<sz[rooty])swap(rootx,rooty);

        dsu[rooty]=rootx;
        sz[rootx]+=sz[rooty];
    }

    bool connected(int x,int y){
        return root(x)==root(y);
    }
}graph;

info dp[MAXN][20];

void dfs(int x,int p,int ee){
    parent[x]=p;
    dep[x]=dep[p]+1;

    dp[x][0].par=parent[x];
    dp[x][0].mins=min(res[x],res[parent[x]]);
    dp[x][0].maxe=ee;

    for(int t=1;t<20;t++){
        dp[x][t].par=dp[dp[x][t-1].par][t-1].par;
        dp[x][t].mins=min( dp[x][t-1].mins , dp[dp[x][t-1].par][t-1].mins );
        dp[x][t].maxe=max( dp[x][t-1].maxe , dp[dp[x][t-1].par][t-1].maxe );
    }

    for(pair<int,int> i:tree[x]){
        if(i.first==p)continue;
        dfs(i.first,x,i.second);
    }
}

int getbranch(int x,int y){
    int ans=inf;

    if(dep[x]<dep[y])swap(x,y);

    if(x==y or parent[x]==y)return inf;

    if(dep[x]!=dep[y]){
        x=parent[x];

        for(int i=19;i>=0;i--){
            if(dep[x]-dep[y]>(1<<i)){
                ans=min(ans,dp[x][i].mins);
                x=dp[x][i].par;
            }
        }
        
        if(parent[x]==y)return ans;

        if(dep[x]>dep[y]){
            x=parent[x];
            ans=min(ans,res[x]);
        }
    }

    x=parent[x];
    y=parent[y];

    ans=min(ans,res[x]);

    for(int i=19;i>=0;i--){
        if(dp[x][i].par!=0 and dp[y][i].par!=0 and dp[x][i].par!=dp[y][i].par){
            ans=min(ans,dp[x][i].mins);
            ans=min(ans,dp[y][i].mins);

            x=dp[x][i].par; y=dp[y][i].par;
        }
    }

    if(x!=y)ans=min(ans,res[parent[x]]);

    return ans;
}

int getedge(int x,int y){
    if(dep[x]>dep[y])swap(x,y);

    int ans=0;
    for(int i=19;i>=0;i--){
        if(dep[x]-dep[y]>(1<<i)){
            ans=max(ans,dp[x][i].maxe);
            x=dp[x][i].par;
        }
    }

    if(parent[x]==y)return ans;
    
    ans=max(ans,dp[x][0].maxe);
    x=dp[x][0].par;

    for(int i=19;i>=0;i--){
        if(dp[x][i].par!=0 and dp[y][i].par!=0 and dp[x][i].par!=dp[y][i].par){
            ans=max(ans,dp[x][i].maxe);
            ans=max(ans,dp[y][i].maxe);

            x=dp[x][i].par; y=dp[y][i].par;
        }
    }

    return ans;
}

void init(int N, int M,vector<int> U, vector<int> V, vector<int> W) {
    n=N; m=M;
    for(int i=1;i<=m;i++){
        a[i]=U[i-1]+1; b[i]=V[i-1]+1; c[i]=W[i-1];

        v[a[i]].push_back(c[i]);
        v[b[i]].push_back(c[i]);

        e[i]={a[i],b[i],c[i]};
    }

    for(int i=1;i<=n;i++){
        sort(v[i].begin(),v[i].end());

        res[i]=inf;
        if(v[i].size()>=3)res[i]=v[i][2];
    }
    res[0]=inf;

    sort(e+1,e+m+1);
    graph.init();

    for(int i=1;i<=m;i++){
        if(graph.connected(e[i].from,e[i].to))continue;
        
        tree[e[i].from].push_back({e[i].to,e[i].cost});
        tree[e[i].to].push_back({e[i].from,e[i].cost});

        graph.mergev(e[i].from,e[i].to);
    }

    for(int t=0;t<20;t++)dp[0][t]={0,inf,0};
    dfs(1,0,0);
}

int getMinimumFuelCapacity(int X, int Y) {
    int ans=getbranch(X+1,Y+1);

    if(ans==inf)return -1;
    return max(ans,getedge(X+1,Y+1));
}

/*
int main(){
    init(5, 6, {0, 0, 1, 1, 1, 2}, {1, 2, 2, 3, 4, 3}, {4, 4, 1, 2, 10, 3});

    cout<<getMinimumFuelCapacity(1, 2)<<"\n";
    cout<<getMinimumFuelCapacity(2,4)<<"\n";
    cout<<getMinimumFuelCapacity(0,1)<<"\n";
}
*/
# Verdict Execution time Memory Grader output
1 Correct 2 ms 8536 KB Output is correct
2 Correct 1 ms 8540 KB Output is correct
3 Correct 1 ms 8540 KB Output is correct
4 Correct 1 ms 8796 KB Output is correct
5 Correct 1 ms 10844 KB Output is correct
6 Correct 2 ms 10844 KB Output is correct
7 Correct 1 ms 10844 KB Output is correct
8 Correct 1 ms 10844 KB Output is correct
9 Correct 52 ms 37444 KB Output is correct
10 Correct 64 ms 44628 KB Output is correct
11 Correct 62 ms 44116 KB Output is correct
12 Correct 69 ms 44880 KB Output is correct
13 Correct 71 ms 45948 KB Output is correct
14 Correct 88 ms 37204 KB Output is correct
15 Correct 146 ms 46356 KB Output is correct
16 Correct 148 ms 45056 KB Output is correct
17 Correct 138 ms 47800 KB Output is correct
18 Correct 157 ms 46832 KB Output is correct
19 Incorrect 51 ms 17488 KB Output isn't correct
20 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 2 ms 8536 KB Output is correct
2 Correct 1 ms 8540 KB Output is correct
3 Incorrect 89 ms 44904 KB Output isn't correct
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 2 ms 8536 KB Output is correct
2 Correct 1 ms 8540 KB Output is correct
3 Correct 1 ms 8540 KB Output is correct
4 Correct 1 ms 8796 KB Output is correct
5 Correct 1 ms 10844 KB Output is correct
6 Correct 2 ms 10844 KB Output is correct
7 Correct 1 ms 10844 KB Output is correct
8 Correct 1 ms 10844 KB Output is correct
9 Incorrect 1 ms 8540 KB Output isn't correct
10 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 8540 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 2 ms 8536 KB Output is correct
2 Correct 1 ms 8540 KB Output is correct
3 Correct 1 ms 8540 KB Output is correct
4 Correct 1 ms 8796 KB Output is correct
5 Correct 1 ms 10844 KB Output is correct
6 Correct 2 ms 10844 KB Output is correct
7 Correct 1 ms 10844 KB Output is correct
8 Correct 1 ms 10844 KB Output is correct
9 Correct 52 ms 37444 KB Output is correct
10 Correct 64 ms 44628 KB Output is correct
11 Correct 62 ms 44116 KB Output is correct
12 Correct 69 ms 44880 KB Output is correct
13 Correct 71 ms 45948 KB Output is correct
14 Correct 88 ms 37204 KB Output is correct
15 Correct 146 ms 46356 KB Output is correct
16 Correct 148 ms 45056 KB Output is correct
17 Correct 138 ms 47800 KB Output is correct
18 Correct 157 ms 46832 KB Output is correct
19 Incorrect 89 ms 44904 KB Output isn't correct
20 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 8540 KB Output isn't correct
2 Halted 0 ms 0 KB -