Submission #253562

#	Time	Username	Problem	Language	Result	Execution time	Memory
253562		khangal	Arranging Shoes (IOI19_shoes)	C++14	100 / 100	122 ms	46440 KiB

shoes

#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
using namespace std;
typedef long long ll;
typedef double db;
typedef vector<long long> vl;
typedef pair<long long , long long > pl;
const int N=1e6+1;
#define po pop_back
#define pb push_back
#define mk make_pair
#define lw lower_bound
#define up upper_bound
#define ff first
#define ss second
#define boost ios_base::sync_with_stdio(); cin.tie(0); cout.tie(0);
#define MOD 1000000007
#define MAX 1e18 
#define MIN -1e18
#define rep(i,a,b) for(ll i=a;i<=b;i++)
#define per(i,a,b) for(ll i=b;i>=a;i--)
#define con continue
#define freopen freopen("input.txt", "r", stdin);freopen("output.txt", "w", stdout);
#define PI 3.14159265358979323846264338327950288419716939937510582097494459230781640628
// typedef tree<ll , null_type, less<ll>, rb_tree_tag, tree_order_statistics_node_update> indexed_set;
// template< typename T>
// using indexed_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
ll sz,n,m,ans,mid,mn,mx,cnt,T,sum,h1,h2,e[1234567],b[1234567],c[1234567],d[1<<20],k,i,j,l,r,h,a[1234567],w,x,y,z;
bool used[1234567];
vector<ll> v[1234567];
ll dx[4]={-1,1,0,0},dy[4]={0,0,-1,1},c1[123][123];
vector<ll>A[101000], B[101000];
ll BIT[201000];
 
 
void Add(ll a, ll b) {
    while (a <= 2 * n) {
        BIT[a] += b;
        a += (a&-a);
    }
}
ll Sum(ll a){
    ll r = 0;
    while (a) {
        r += BIT[a];
        a -= (a&-a);
    }
    return r;
}
 
vector<pl>V;

ll count_swaps(vector<int> vec){
    n = vec.size()/2;
    for(ll i = 0; i < 2 * n; i++) {
        if(vec[i] < 0)A[-vec[i]].pb(i+1);
        else B[vec[i]].pb(i + 1);
    }
    ll res = 0;
    for(ll i = 1; i <= n; i++) {
        for(ll j = 0; j < A[i].size(); j++) {
            ll t1 = A[i][j], t2 = B[i][j];
            if(t1 > t2) {
                res++;
                swap(t1 , t2);
            }
            V.pb({t1 , t2});
        }
    }
    sort(V.begin() , V.end());
    for(auto t : V){
        ll s1 = Sum(t.ff);
        ll s2 = Sum(t.ss);
        ll s3 = Sum(2 * n);
        res += s2 - s1 + (s3 - s2) * 2;
        Add(t.ss , 1);
    }
    return res;
}

Compilation message (stderr)

shoes.cpp: In function 'll count_swaps(std::vector<int>)':
shoes.cpp:63:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(ll j = 0; j < A[i].size(); j++) {
                       ~~^~~~~~~~~~~~~

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