Submission #832110

#	Time	Username	Problem	Language	Result	Execution time	Memory
832110		maomao90	Arranging Shoes (IOI19_shoes)	C++17	100 / 100	52 ms	18316 KiB

shoes

// I can do all things through Christ who strengthens me
// Philippians 4:13

#include "shoes.h"
#include "bits/stdc++.h"
using namespace std;

#define REP(i, j, k) for (int i = j; i < (k); i++)
#define RREP(i, j, k) for (int i = j; i >= (k); i--)

template <class T>
inline bool mnto(T &a, const T b) {return a > b ? a = b, 1 : 0;}
template <class T>
inline bool mxto(T &a, const T b) {return a < b ? a = b, 1 : 0;}

typedef long long ll;
typedef long double ld;
#define FI first
#define SE second
typedef pair<int, int> ii;
typedef pair<ll, ll> pll;
#define SZ(x) (int) x.size()
#define ALL(x) x.begin(), x.end()
#define pb push_back
typedef vector<int> vi;
typedef vector<ii> vii;
typedef vector<ll> vll;
typedef tuple<int, int, int> iii;
typedef vector<iii> viii;

#ifndef DEBUG
#define cerr if (0) cerr
#endif

const int INF = 1000000005;
const ll LINF = 1000000000000000005;
const int MAXN = 200005;

int n;
vi vp[2][MAXN];

int fw[MAXN];
void incre(int i, int x) {
    i++;
    for (; i <= 2 * n; i += i & -i) {
        fw[i] += x;
    }
}
int qsm(int i) {
    i++;
    int res = 0;
    for (; i > 0; i -= i & -i) {
        res += fw[i];
    }
    return res;
}
int qsm(int s, int e) {
    return qsm(e) - qsm(s - 1);
}

ll count_swaps(vi s) {
    n = SZ(s) / 2;
    REP (i, 0, 2 * n) {
        if (s[i] < 0) {
            vp[0][-s[i]].pb(i);
        } else {
            vp[1][s[i]].pb(i);
        }
    }
    vector<bool> vis(2 * n, 0);
    ll ans = 0;
    RREP (i, 2 * n - 1, 0) {
        if (vis[i]) {
            continue;
        }
        bool b = s[i] > 0;
        int j = vp[b ^ 1][abs(s[i])].back();
        vp[b][abs(s[i])].pop_back(); vp[b ^ 1][abs(s[i])].pop_back();
        vis[i] = vis[j] = 1;
        ans += i - j - b - qsm(j, i);
        incre(j, 1); incre(i, 1);
    }
	return ans;
}

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