Submission #1112320

#	Time	Username	Problem	Language	Result	Execution time	Memory
1112320		ljtunas	Construction Project 2 (JOI24_ho_t2)	C++14	16 / 100	2068 ms	25904 KiB

Main

// author : anhtun_hi , nqg
#include <bits/stdc++.h>
#define ll long long
#define ii pair<ll, ll>
#define fi first
#define se second
#define all(x) x.begin(), x.end()
#define reset(h, v)    memset(h, v, sizeof h)
#define Forv(i, a)     for(auto& i : a)
#define For(i, a, b)   for(int i = a; i <= b; ++i)
#define Ford(i, a, b)  for(int i = a; i >= b; --i)
#define c_bit(i)     __builtin_popcountll(i)
#define Bit(mask, i)    ((mask >> i) & 1LL)
#define onbit(mask, i)  ((mask) bitor (1LL << i))
#define offbit(mask, i) ((mask) &~ (1LL << i))
using namespace std;
namespace std {
    template <typename T, int D>
    struct _vector : public vector <_vector <T, D - 1>> {
        static_assert(D >= 1, "Dimension must be positive!");
        template <typename... Args>
        _vector(int n = 0, Args... args) : vector <_vector <T, D - 1>> (n, _vector <T, D - 1> (args...)) {}
    };
    template <typename T> struct _vector <T, 1> : public vector <T> {
        _vector(int n = 0, const T& val = T()) : vector <T> (n, val) {}
    };
    template <class A, class B> bool minimize(A &a, B b){return a > b ? a = b, true : false;}
    template <class A, class B> bool maximize(A &a, B b){return a < b ? a = b, true : false;}
}
const int dx[] = {0, 0, +1, -1}, dy[] = {-1, +1, 0, 0}, LOG = 20, base = 311, inf = 1e9 + 5;
const int MAXN = 2e5 + 5;
const  ll  mod = 1e9 + 7;
const  ll   oo = 1e18;

//#define int long long

int n, m, s, t; ll L, k;

vector<ii> g[MAXN];
ll d[2][MAXN];

void Solve() {
    cin >> n >> m >> s >> t >> L >> k;
    For(i, 1, m){
        int u, v; ll w;
        cin >> u >> v >> w;
        g[u].push_back({v, w});
        g[v].push_back({u, w});
    }
    priority_queue<array<ll, 3>, vector<array<ll, 3>>> pq;
    reset(d, 0x3f);
    pq.push({0, s, 0}); d[0][s] = 0;
    pq.push({0, t, 1}); d[1][t] = 0;
    while(pq.size()){
        auto [du, u, op] = pq.top(); pq.pop();
        if(du != d[op][u]) continue;
        for(auto [v, w] : g[u]){
            if(d[op][v] > d[op][u] + w){
                d[op][v] = d[op][u] + w;
                pq.push({d[op][v], v, op});
            }   
        }
    }
    if(d[0][t] <= k) cout << 1LL * n * (n - 1) / 2 << '\n';
    else {
        ll ans = 0;
        For(i, 0, 1) sort(d[i] + 1, d[i] + n + 1);
        For(i, 1, n) {
            int l = 0, r = n + 1;
            while(r - l > 1){
                int mid = l + r >> 1;
                if(d[0][i] + d[1][mid] <= k - L) l = mid;
                else r = mid;
            }
            ans += l;
        }
        cout << ans << '\n';
    }
}

int32_t main() {
    cin.tie(0) -> sync_with_stdio(0);
    if(fopen("JOI24_ho_t2.inp", "r")) {
        freopen("JOI24_ho_t2.inp", "r", stdin);
        freopen("JOI24_ho_t2.out", "w", stdout);
    }

    int t = 1;
//    cin >> t;

    for (int test = 1; test <= t; test++) {
        Solve();
    }
    return 0;
}

Compilation message (stderr)

Main.cpp: In function 'void Solve()':
Main.cpp:55:14: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   55 |         auto [du, u, op] = pq.top(); pq.pop();
      |              ^
Main.cpp:57:18: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   57 |         for(auto [v, w] : g[u]){
      |                  ^
Main.cpp:71:29: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   71 |                 int mid = l + r >> 1;
      |                           ~~^~~
Main.cpp: In function 'int32_t main()':
Main.cpp:84:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   84 |         freopen("JOI24_ho_t2.inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:85:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   85 |         freopen("JOI24_ho_t2.out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 8
• Subtask 2: 16 / 16
• Subtask 3: 0 / 29
• Subtask 4: 0 / 47