Submission #1264126

#	Time	Username	Problem	Language	Result	Execution time	Memory
1264126		bnd2100	Commuter Pass (JOI18_commuter_pass)	C++20	0 / 100	203 ms	30368 KiB

commuter_pass

/*
* @Author: Twynzz
* @Last Modified by: Twynzz
* @Note For This Problem: https://wbd.ms/share/v2/aHR0cHM6Ly93aGl0ZWJvYXJkLm1pY3Jvc29mdC5jb20vYXBpL3YxLjAvd2hpdGVib2FyZHMvcmVkZWVtL2NmODRmYTFjYTY2NjRiNmViYjc1MzU1OTNjYmZjYzZhX0JCQTcxNzYyLTEyRTAtNDJFMS1CMzI0LTVCMTMxRjQyNEUzRF9iMDY2ZDUzNC1iMDIzLTQ1ZDQtOGNiNS03MDEwOWE0NjcwNTg=
*/


#include <bits/stdc++.h>
using namespace std;

// ------------ Define ------------

#define el "\n"
#define int long long
#define ld long double
#define str string
#define file(name) {freopen(name".inp","r",stdin);freopen(name".out","w",stdout);}
#define IOS {std::ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);}
#define _TBN_ signed main()
#define setp(n) setprecision(n)<< fixed
#define fi first
#define se second
#define ii pair<int,int>
#define gcd(a,b) __gcd(a,b)
#define tup pair<int,ii>
#define pb push_back
#define pf push_front
#define eb emplace_back
#define sz(v) (int)v.size()

const int maxn = 3e5+9;
const long long oo = 1e18;
const int MOD = 1e9+7, Mod = 998244353;
const int base = 311;

template<class X>
    bool maximize(X &a, const X &b)
    {
        if (a<b)
        {
            a = b;
            return 1;
        }
        return 0;
    }

template<class X>
    bool minimize(X &a, const X &b)
    {
        if (a>b)
        {
            a = b;
            return 1;
        }
        return 0;
    }

namespace sub1
{
    bool checkSub1();
    void sub1();
}
namespace sub2
{
    bool checkSub2();
    void sub2();
}
namespace sub3
{
    bool checkSub3();
    void sub3();
}

int lcm(int a, int b)
{
    return a/gcd(a,b)*b;
}

int sqr(int x) {return x*x;}

inline bool MASK(int mask, int bit) {return ((mask>>bit)&1);}
inline long long F(int n) {return n*(n+1)/2;}
inline int add(int a, int b, int m = MOD) {return ((a%m+b%m)%m+m)%m;}
inline int sub(int a, int b, int m = MOD) {return ((a-b)%m+m)%m;}
inline int mul(int a, int b, int m = MOD) {return ((a%m)*(b%m))%m;}

int dx[] = {1, 0};
int dy[] = {0, 1};

// ------------ Code ------------

int n, m, S, T, U, V;
vector<ii> adj[maxn];

_TBN_
{
    IOS;
    if (fopen("BOOKR.inp","r")) file("BOOKR");
    cin >>n >>m >>S >>T >>U >>V;
    for(int i = 1; i <= m; i++)
    {
        int u, v, c;
        cin >>u >>v >>c;
        adj[u].eb(v, c);
        adj[v].eb(u, c);
    }
    for(int i = 1; i <= 1; i++)
    {
        if (sub1::checkSub1()) {sub1::sub1(); continue;}
        // if (sub2::checkSub2()) {sub2::sub2(); continue;}
        // if (sub3::checkSub3()) {sub3::sub3(); continue;}
    }
    return 0;
}

namespace sub1
{
    bool checkSub1()
    {
        return 1;
    }
    int dis[3][maxn];
    bool vis[maxn];
    void dijk(int s, int id)
    {
        fill(dis[id] + 1, dis[id] + 1 + n, oo);
        fill(vis + 1, vis + 1 + n, 0);
        dis[id][s] = 0;
        priority_queue<ii, vector<ii>, greater<ii>> q;
        q.emplace(0, s);
        while(!q.empty())
        {
            int u = q.top().se;
            q.pop();
            if (vis[u]) continue;
            vis[u] = 1;
            for(ii cur : adj[u])
            {
                int v = cur.fi, w = cur.se;
                if (minimize(dis[id][v], dis[id][u] + w))
                    q.emplace(dis[id][v], v);
            }
        }
    }
    vector<int> e[maxn];
    int dp[maxn][4], ans;
    void dfs(int u)
    {
        dp[u][1] = dis[1][u]; // U -> V xuoi theo dijk
        dp[u][2] = dis[2][u]; // V -> U xuoi theo dijk
        if (u == T) return;
        for(int v : e[u])
        {
            dfs(v);
            minimize(dp[u][1], dp[v][1]);
            minimize(dp[u][2], dp[v][2]);
        }
        minimize(ans, dp[u][1] + dis[2][u]);
        minimize(ans, dis[1][u] + dp[u][2]);
        // cout<< u<< ' '<< dp[u][1]<< ' '<< dis[2][u]<< ' '<< ans<< el;
        // cout<< u<< ' '<< dis[1][u]<< ' '<< dp[u][2]<< el;
    }
    void sub1()
    {
        dijk(S, 0);
        dijk(U, 1);
        dijk(V, 2);
        dijk(T, 3);
        for(int u = 1; u <= n; u++)
        {
            for(ii cur : adj[u])
            {
                int v = cur.fi, w = cur.se;
                if (dis[0][u] + w + dis[3][v] == dis[0][T])
                {
                    e[u].eb(v);
                    // cout<< u<< ' '<< v<< ' '<< w<< el;
                }
            }
        }
        ans = oo;
        dfs(S);
        cout<< ans<< el;
    }
}

Compilation message (stderr)

commuter_pass.cpp: In function 'int main()':
commuter_pass.cpp:17:28: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   17 | #define file(name) {freopen(name".inp","r",stdin);freopen(name".out","w",stdout);}
      |                     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
commuter_pass.cpp:98:33: note: in expansion of macro 'file'
   98 |     if (fopen("BOOKR.inp","r")) file("BOOKR");
      |                                 ^~~~
commuter_pass.cpp:17:58: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   17 | #define file(name) {freopen(name".inp","r",stdin);freopen(name".out","w",stdout);}
      |                                                   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
commuter_pass.cpp:98:33: note: in expansion of macro 'file'
   98 |     if (fopen("BOOKR.inp","r")) file("BOOKR");
      |                                 ^~~~

• Subtask 1: 0 / 16
• Subtask 2: 0 / 15
• Subtask 3: 0 / 24
• Subtask 4: 0 / 45