| # | Time | Username | Problem | Language | Result | Execution time | Memory | 
|---|---|---|---|---|---|---|---|
| 1041828 | stdfloat | Swapping Cities (APIO20_swap) | C++17 | 0 ms | 0 KiB | 
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
#include "swap.h"
// #include "grader.cpp"
using namespace std;
#define int long long
using ll = long long;
#define ff  first
#define ss  second
#define pii pair<int, int>
int n;
vector<vector<pii>> E;
void init(int N, int M, vector<int> U, vector<int> V, vector<int> W) {
    n = N;
    E.assign(n, {});
    for (int i = 0; i < M; i++) {
        E[U[i]].push_back({V[i], W[i]});
        E[V[i]].push_back({U[i], W[i]});
    }
}
int getMinimumFuelCapacity(int X, int Y) {
    int l = 0, r = (int)1e9 + 1;
    while (l < r) {
        int md = (l + r) >> 1;
        queue<int> q;
        vector<bool> visX(n);
        vector<int> p(n, -1);
        q.push(X); visX[X] = true;
        while (!q.empty()) {
            int x = q.front(); q.pop();
            for (auto [i, w] : E[x]) {
                if (w <= md && !visX[i]) {
                    p[i] = x;
                    q.push(i);
                    visX[i] = true;
                }
            }
        }
        if (!visX[Y]) {
            l = md + 1;
            continue;
        }
        bool tr = false;
        vector<bool> visY(n);
        queue<pii> q1;
        q1.push({Y, -1}); visY[Y] = true;
        while (!q1.empty() && !tr) {
            auto [x, p] = q1.front(); q1.pop();
        
            for (auto [i, w] : E[x]) {
                if (w > md || i == p) continue;
                if (visY[i]) {
                    if (visX[i]) {
                        tr = true;
                        break;
                    }
                }
                else {
                    visY[i] = true;
                    q1.push({i, x});
                }
            }
        }
        int x = Y;
        while (x != X && !tr) {
            x = p[x];
            int cnt = 0;
            for (auto [i, w] : E[x]) {
                cnt += (w <= md);
            }
            tr = (cnt > 2);
        }
        if (!tr) l = md + 1;
        else r = md;
    }
    return (l == (int)1e9 + 1 ? -1 : l);
}
