Submission #317268

#	Time	Username	Problem	Language	Result	Execution time	Memory
317268		zaneyu	Dreaming (IOI13_dreaming)	C++14	100 / 100	159 ms	18628 KiB

dreaming

#include "dreaming.h"
#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
 
#pragma GCC optimize("unroll-loops,no-stack-protector")
//order_of_key #of elements less than x
// find_by_order kth element
#define ll long long 
#define ld long double
#define pii pair<int,int>
typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> indexed_set;
#define f first
#define s second
#define pb push_back
#define REP(i,n) for(int i=0;i<n;i++)
#define REP1(i,n) for(int i=1;i<=n;i++)
#define FILL(n,x) memset(n,x,sizeof(n))
#define ALL(_a) _a.begin(),_a.end()
#define sz(x) (int)x.size()
#define SORT_UNIQUE(c) (sort(c.begin(),c.end()), c.resize(distance(c.begin(),unique(c.begin(),c.end()))))
#define MP make_pair
const ll INF64=4e12;
const int INF=0x3f3f3f3f;
const ll MOD=1e9+7;
const ld PI=acos(-1);
const ld eps=1e-9;
#define lowb(x) x&(-x)
#define MNTO(x,y) x=min(x,(__typeof__(x))y)
#define MXTO(x,y) x=max(x,(__typeof__(x))y)
ll mult(ll a,ll b){
    return ((a%MOD)*(b%MOD))%MOD;
}
ll mypow(ll a,ll b){
    if(b<=0) return 1;
    ll res=1LL;
    while(b){
        if(b&1){
            res=(res*a)%MOD;
        }
        a=(a*a)%MOD;
        b>>=1;
    }
    return res;
}
const ll maxn=1e5+5;
const ll maxlg=__lg(maxn)+2;
vector<pii> v[maxn];
bool vis[maxn];
int dist[maxn][4];
vector<int> ppl;
void dfs(int u,int p,int d){
    ppl.pb(u);
    for(auto x:v[u]){
        if(x.f!=p){
            dist[x.f][d]=dist[u][d]+x.s;
            dfs(x.f,u,d);
        }
    }
}
int get(int i,int b){
    ppl.clear();
    dist[i][b]=0;
    dfs(i,-1,b);
    int mx=-1;
    int z;
    for(auto x:ppl) if(dist[x][b]>mx){
        mx=dist[x][b];
        z=x;
    }
    return z;
}
int travelTime(int n, int m, int l, int A[], int B[], int T[]) {
    REP(i,m){
        v[A[i]].pb({B[i],T[i]});
        v[B[i]].pb({A[i],T[i]});
    }
    vector<int> dst;
    REP(i,n) vis[i]=0;
    int mx=0;
    REP(i,n){
        if(!vis[i]){
            int u=get(i,2);
            int vv=get(u,1);

            get(vv,0);
            int mn=INF;
            int z=0;
            for(auto x:ppl){
                //cout<<x<<'\n';
                vis[x]=1;
                if(mn>max(dist[x][0],dist[x][1])){
                    mn=max(dist[x][0],dist[x][1]);
                    z=x;
                }
                
            }
            MXTO(mx,dist[vv][1]);
            //cout<<'\n';
            //cout<<mn<<'\n';
            //cout<<'\n';
            dst.pb(mn);
        }
    }
    sort(ALL(dst));
    reverse(ALL(dst));
    if(sz(dst)>=2) MXTO(mx,dst[0]+dst[1]+l);
    if(sz(dst)>=3) MXTO(mx,dst[1]+dst[2]+2*l);
    return mx;
}

Compilation message (stderr)

dreaming.cpp: In function 'int travelTime(int, int, int, int*, int*, int*)':
dreaming.cpp:90:17: warning: variable 'z' set but not used [-Wunused-but-set-variable]
   90 |             int z=0;
      |                 ^
dreaming.cpp: In function 'int get(int, int)':
dreaming.cpp:73:12: warning: 'z' may be used uninitialized in this function [-Wmaybe-uninitialized]
   73 |     return z;
      |            ^

• Subtask 1: 14 / 14
• Subtask 2: 10 / 10
• Subtask 3: 23 / 23
• Subtask 4: 18 / 18
• Subtask 5: 12 / 12
• Subtask 6: 23 / 23