Submission #981690

#	Time	Username	Problem	Language	Result	Execution time	Memory
981690		Alkaser_ID	Swapping Cities (APIO20_swap)	C++17	37 / 100	2041 ms	13512 KiB

swap

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

int n,m;
vector<pair<int,pair<int,int>>> v;
void init(int N, int M,
          std::vector<int> U, std::vector<int> V, std::vector<int> W) {
    n=N;m = M;
    for(int i=0;i<m;++i){
        v.push_back({W[i],{U[i],V[i]}});
    }
    sort(v.begin(),v.end());
}
int p[100005],sz[100005],dg[100005]; bool bl[100005];
inline int parent(int a){
    if(a == p[a]) return a;
    return a = parent(p[a]);
}

inline void merg(int x,int y){
    int a = parent(x),b = parent(y);
    if(a == b) return;
    if(sz[b] > sz[a]) swap(a,b);
    sz[a] += sz[b];
    p[b] = a;
    bl[a] = bl[a] | bl[b];
}

int getMinimumFuelCapacity(int X, int Y) {
    for(int i=0;i<n;++i) {
        p[i] = i; sz[i] = 1;
        dg[i] = 0;
        bl[i] = false;
    }
    int res = -1;
    for(int i=0;i<m;++i){
        int vl = v[i].first;
        int u = v[i].second.first, d = v[i].second.second;
        dg[u]++;dg[d]++;
        int U = parent(u),D = parent(d);
        if(dg[u] > 2) bl[U] = true;
        if(dg[d] > 2) bl[D] = true;
        if(U == D) bl[U] = true;
        else merg(U,D);
        int px = parent(X),py = parent(Y);
        if(px == py && bl[px]) {
            res = vl;
            break;
        }
    }
    return res;
}

• Subtask 1: 0 / 6
• Subtask 2: 0 / 7
• Subtask 3: 17 / 17
• Subtask 4: 20 / 20
• Subtask 5: 0 / 23
• Subtask 6: 0 / 27