Submission #312204

#	Time	Username	Problem	Language	Result	Execution time	Memory
312204		tjdgus4384	Arranging Shoes (IOI19_shoes)	C++14	100 / 100	251 ms	141200 KiB

shoes

#include<bits/stdc++.h>
using namespace std;
deque<int> vp[100001], vm[100001], v, v2;

long long merge_sort(int x, int y){
    if(x == y) return 0;
    int mid = (x+y)/2;
    long long ret = merge_sort(x, mid) + merge_sort(mid+1, y);
    int f = x, s = mid+1;
    vector<int> newv;
    while(f <= mid && s <= y){
        if(v2[f] <= v2[s]){
            newv.push_back(v2[f]);
            f++;
        }
        else {
            newv.push_back(v2[s]);
            ret += mid - f + 1;
            s++;
        }
    }
    for(int i = f;i <= mid;i++) newv.push_back(v2[i]);
    for(int i = s;i <= y;i++) newv.push_back(v2[i]);
    for(int i = x;i <= y;i++) v2[i] = newv[i - x];
    return ret;
}

long long count_swaps(vector<int> S){
    for(int i = 0;i < S.size();i++){
        if(S[i] < 0){
            if(vp[-S[i]].empty()) vm[-S[i]].push_back(i);
            else{
                v.push_back(i);
                v.push_back(vp[-S[i]].front());
                vp[-S[i]].pop_front();
            }
        }
        if(S[i] > 0){
            if(vm[S[i]].empty()) vp[S[i]].push_back(i);
            else{
                v.push_back(vm[S[i]].front());
                v.push_back(i);
                vm[S[i]].pop_front();
            }
        }
    }
    for(int i = 0;i < v.size();i++) v2.push_back(v[i]);
    return merge_sort(0, v2.size()-1);
}

Compilation message (stderr)

shoes.cpp: In function 'long long int count_swaps(std::vector<int>)':
shoes.cpp:29:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   29 |     for(int i = 0;i < S.size();i++){
      |                   ~~^~~~~~~~~~
shoes.cpp:47:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::deque<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   47 |     for(int i = 0;i < v.size();i++) v2.push_back(v[i]);
      |                   ~~^~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 20 / 20
• Subtask 3: 20 / 20
• Subtask 4: 15 / 15
• Subtask 5: 20 / 20
• Subtask 6: 15 / 15