Submission #707809

#	Time	Username	Problem	Language	Result	Execution time	Memory
707809		victor_gao	Minerals (JOI19_minerals)	C++17	90 / 100	47 ms	2844 KiB

minerals

#include"minerals.h"
#include<bits/stdc++.h>
using namespace std;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
vector<int>arr;
bool alive[100015],vis[100015];
int n;
void Merge(int l,int r,vector<int>have,bool stay1){
    if (l==r){
        Answer(arr[l-1],have[0]);
        return;
    }
    int mid=(l+r)>>1,last;
    vector<int>L,R;
    if (!stay1){
        for (int i=l-1;i<mid;i++){
            last=Query(arr[i]);
            alive[arr[i]]^=1;
        }
    }
    else {
        for (int i=mid;i<r;i++){
            last=Query(arr[i]);
            alive[arr[i]]^=1;
        }
    }
    for (auto i:have){
        if (L.size()==(mid-l+1)){
            R.push_back(i);
            continue;
        }
        if (R.size()==(r-mid)){
            L.push_back(i);
            continue;
        }
        int now=Query(i);
        alive[i]^=1;
        bool ty=(now==last);
        if (ty)
            L.push_back(i);
        else R.push_back(i);
        last=now;
    }
    Merge(mid+1,r,R,0);
    Merge(l,mid,L,1);
}
void Solve(int N){
    n=N;
    vector<int>qry;
    int last=-1;
    for (int i=1;i<=2*N;i++){
        if (arr.size()==N){
            qry.push_back(i);
            continue;
        }
        int now=Query(i);
        alive[i]^=1;
        if (now==last)
            qry.push_back(i);
        else {
            arr.push_back(i);
            last=now;
        }
    }
    shuffle(arr.begin(),arr.end(),rng);
    shuffle(qry.begin(),qry.end(),rng);
    Merge(1,N,qry,1);
}
/*
g++ -std=gnu++14 -O2 -o grader grader.cpp minerals.cpp
./grader.exe
./rand.exe

4
1 5
2 6
3 4
7 8
*/

Compilation message (stderr)

minerals.cpp: In function 'void Merge(int, int, std::vector<int>, bool)':
minerals.cpp:28:21: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   28 |         if (L.size()==(mid-l+1)){
      |             ~~~~~~~~^~~~~~~~~~~
minerals.cpp:32:21: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   32 |         if (R.size()==(r-mid)){
      |             ~~~~~~~~^~~~~~~~~
minerals.cpp: In function 'void Solve(int)':
minerals.cpp:52:23: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   52 |         if (arr.size()==N){
      |             ~~~~~~~~~~^~~
minerals.cpp: In function 'void Merge(int, int, std::vector<int>, bool)':
minerals.cpp:39:9: warning: 'last' may be used uninitialized in this function [-Wmaybe-uninitialized]
   39 |         if (ty)
      |         ^~

• Subtask 1: 6 / 6
• Subtask 2: 25 / 25
• Subtask 3: 9 / 9
• Subtask 4: 30 / 30
• Subtask 5: 5 / 5
• Subtask 6: 5 / 5
• Subtask 7: 5 / 5
• Subtask 8: 5 / 5
• Subtask 9: 0 / 10