Submission #466761

#	Time	Username	Problem	Language	Result	Execution time	Memory
466761		M4mou	Handcrafted Gift (IOI20_gift)	C++17	100 / 100	232 ms	22816 KiB

gift

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

vector<int>parent;
void init(int n) { parent.resize(n); for(int l=0;l<n;l++) parent[l]=l; }
int findset(int n) { return (parent[n]==n)?n:(parent[n]=findset(parent[n])); }
bool sameSet(int a, int b) { return findset(a)==findset(b); }
void unionSet(int a, int b) {
    if(sameSet(a, b)) return;
    a=findset(a); b=findset(b);
    if(a < b)
    parent[a]=b;
    else parent[b] = a;
}

int construct(int n, int r, std::vector<int> a, std::vector<int> b, std::vector<int> x) {
    init(n+1);
    for(int i = 0; i < r; i++){
        if(x[i] == 2) continue;
        int j = findset(a[i]);
        while(j <= b[i] && findset(j) != findset(b[i])){
            unionSet(j,b[i]);
            j++;
            j = findset(j);
        }
    }

    for(int i=0;i<r;i++){
        if(x[i]==1){
            continue;
        }
        if(findset(a[i])==findset(b[i])){
            return 0;
        }
    }
    string s ="R";
    
    for(int i=1;i<n;i++)
    {
        if(findset(i) != findset(i-1))
        if(s.back() == 'R')s += "B";
        else s+= "R";
        else s+= s.back();
    }
    craft(s);
    return 1;
}

• Subtask 1: 10 / 10
• Subtask 2: 15 / 15
• Subtask 3: 20 / 20
• Subtask 4: 25 / 25
• Subtask 5: 30 / 30