Submission #161831

#	Time	Username	Problem	Language	Result	Execution time	Memory
161831		mhy908	Arranging Shoes (IOI19_shoes)	C++14	100 / 100	198 ms	23788 KiB

shoes

#include "shoes.h"
#include <bits/stdc++.h>
#define F first
#define S second
#define pb push_back
#define mp make_pair
#define all(x) x.begin(), x.end()
using namespace std;
typedef long long LL;
typedef pair<int, int> pii;
typedef pair<LL, LL> pll;
vector<int> pl[100010], mi[100010];
vector<pair<pii, int> >arr;
struct SEGMENT_TREE {
    struct NODE {
        int st, fin;
        LL q;
    } tree[1000000];
    int x;
    const LL inf=987654321987654321;
    LL f(LL a, LL b){return a+b;}
    void maketree(int point, int num) {
        if(num==1)tree[point].st=tree[point].fin=++x;
        if(num<=1)return;
        maketree(point*2, num-num/2);
        maketree(point*2+1, num/2);
        tree[point].st=tree[point*2].st;
        tree[point].fin=tree[point*2+1].fin;
    }
    LL query(int a, int b, int point) {
        if(tree[point].st>=a&&tree[point].fin<=b)
            return tree[point].q;
        if(tree[point].st>b||tree[point].fin<a)
            return 0;
        return f(query(a, b, point*2), query(a, b, point*2+1));
    }
    void updaterange(int point, int num, LL p) {
        if(tree[point].st==tree[point].fin) {
            tree[point].q=p;
            return;
        }
        if(num<=tree[point*2].fin)updaterange(point*2, num, p);
        else updaterange(point*2+1, num, p);
        tree[point].q=f(tree[point*2].q, tree[point*2+1].q);
    }
    void init(int n) {
        maketree(1, n);
    }
    LL get_query(int a, int b) {
        return query(a, b, 1);
    }
    void update(int a, LL num) {
        updaterange(1, a, num);
    }
}seg;
LL count_swaps(std::vector<int> s) {
    LL ans=0;
	for(int i=0; i<s.size(); i++){
        if(s[i]<0)mi[-s[i]].pb(i+1);
        else pl[s[i]].pb(i+1);
	}
	for(int i=1; i<=100000; i++){
        for(int j=0; j<pl[i].size(); j++){
            if(mi[i][j]<pl[i][j])arr.pb(mp(mp(mi[i][j], pl[i][j]), 0));
            else arr.pb(mp(mp(pl[i][j], mi[i][j]), 1));
        }
	}
	sort(all(arr));
	seg.init(s.size());
	for(int i=1; i<=s.size(); i++)seg.update(i, 1);
	for(int i=0; i<arr.size(); i++){
        //printf("%d %d\n", arr[i].F.F, arr[i].F.S);
        ans+=seg.get_query(arr[i].F.F+1, arr[i].F.S-1)+(LL)arr[i].S;
        seg.update(arr[i].F.F, 0);
        seg.update(arr[i].F.S, 0);
	}
	return ans;
}

Compilation message (stderr)

shoes.cpp: In function 'LL count_swaps(std::vector<int>)':
shoes.cpp:58:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0; i<s.size(); i++){
               ~^~~~~~~~~
shoes.cpp:63:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int j=0; j<pl[i].size(); j++){
                      ~^~~~~~~~~~~~~
shoes.cpp:70:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=1; i<=s.size(); i++)seg.update(i, 1);
               ~^~~~~~~~~~
shoes.cpp:71:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0; i<arr.size(); 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