Submission #239628

#	Time	Username	Problem	Language	Result	Execution time	Memory
239628		ant101	Arranging Shoes (IOI19_shoes)	C++14	100 / 100	690 ms	153464 KiB

shoes

#include <iostream>
#include <algorithm>
#include <cstring>
#include <iomanip>
#include <fstream>
#include <cmath>
#include <vector>
#include <set>
#include <unordered_set>
#include <unordered_map>
#include <map>
#include <stack>
#include <queue>
#include <assert.h>
#include <limits>
#include <cstdio>
#include <shoes.h>
using namespace std;

//#define RDEBUG 1
#ifdef RDEBUG
#define D(x) x
#else
#define D(x)
#endif
#define inf 0x7fffffff
#define MOD 1000000007

typedef long long ll;


ll add(ll a, ll b) {
    a += b;
    if(a >= MOD) {
        a -= MOD;
    }
    return a;
}
ll sub(ll a, ll b) {
    a -= b;
    if(a < 0) {
        a += MOD;
    }
    return a;
}

ll mul(ll a, ll b) {
    return (a * b)%MOD;
}

void add_self(ll& a, ll b) {
    a = add(a, b);
}
void sub_self(ll& a, ll b) {
    a = sub(a, b);
}
void mul_self(ll& a, ll b) {
    a = mul(a, b);
}


const ll MAXN = 200010;

ll tree[MAXN];
ll N;

void update(ll ind, ll num) {
    while (ind<=MAXN) {
        tree[ind]+=num;
        ind+=(ind&-ind);
    }
}

ll getsum(ll ind) {
    ll sum = 0;
    while (ind) {
        sum+=tree[ind];
        ind-=(ind&-ind);
    }
    return sum;
}

map<ll, queue<ll>> closest;
ll closestind[MAXN];
ll vis[MAXN];
ll S[MAXN];

long long count_swaps(std::vector<int> s) {
    N = s.size();
    for (ll i = 0; i<s.size(); i++) S[i+1] = s[i];
    for (ll i = 1; i<=N; i++) {
        if (closest.find(S[i]) == closest.end()) {
            queue<ll> q1;
            closest[S[i]] = q1;
        }
        if (closest.find(-S[i]) != closest.end() && closest[-S[i]].size() > 0) {
            closestind[closest[-S[i]].front()] = i;
            closest[-S[i]].pop();
        } else {
            closest[S[i]].push(i);
        }
    }
    ll ans = 0;
    for (ll i = 1; i<=N; i++) {
        if (!vis[i]) {
            ans+=closestind[i]-i-1-(getsum(closestind[i])-getsum(i))+(S[i] > 0);
            update(closestind[i], 1);
            vis[closestind[i]] = 1;
        }
    }
    return ans;
}

Compilation message (stderr)

shoes.cpp: In function 'long long int count_swaps(std::vector<int>)':
shoes.cpp:90:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (ll i = 0; i<s.size(); i++) S[i+1] = s[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