Submission #227097

#	Time	Username	Problem	Language	Result	Execution time	Memory
227097		caoash	Arranging Shoes (IOI19_shoes)	C++14	0 / 100	179 ms	269688 KiB

shoes

#pragma GCC target ("sse4")

#include <bits/stdc++.h>
#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;
 
typedef long long ll;
typedef long double ld;
typedef complex<ld> cd;

typedef pair<int, int> pi;
typedef pair<ll,ll> pl;
typedef pair<ld,ld> pd;
typedef pair<int, pi> pii;

typedef vector<int> vi;
typedef vector<ld> vd;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<cd> vcd;

#define fax(i, a) for (int i = 0; i < (a); i++)
#define f0x(i, a, b) for (int i = (a); i < (b); i++)
#define f0xd(i,a,b) for (int i = (b)-1; i >= (a); i--)
#define faxd(i,a) for (int i = (a)-1; i >= 0; i--)
#define trav(a, x) for (auto& a : x)
#define memeset memset

#define mp make_pair
#define pb push_back
#define f first
#define s second
#define lb lower_bound
#define ub upper_bound

#define sz(x) (int)x.size()
#define all(x) begin(x), end(x)
#define rsz resize

template<class T> void ckmin(T &a, T b) { a = min(a, b); }
template<class T> void ckmax(T &a, T b) { a = max(a, b); }

template <class T, int ...Ns> struct BIT {
    T val = 0;
    void upd(T v) { val += v; }
    T query() { return val; }
};
 
template <class T, int N, int... Ns> struct BIT<T, N, Ns...> {
    BIT<T,Ns...> bit[N + 1];
    template<typename... Args> void upd(int pos, Args... args) {
        for (; pos <= N; pos += (pos&-pos)) bit[pos].upd(args...);
    }
    template<typename... Args> T sum(int r, Args... args) {
        T res = 0; for (; r; r -= (r&-r)) res += bit[r].query(args...); 
        return res;
    }
    template<typename... Args> T query(int l, int r, Args... args) {
        return sum(r,args...)-sum(l-1,args...);
    }
};

namespace input {
    template<class T> void re(complex<T>& x);
    template<class T1, class T2> void re(pair<T1,T2>& p);
    template<class T> void re(vector<T>& a);
    template<class T, size_t SZ> void re(array<T,SZ>& a);

    template<class T> void re(T& x) { cin >> x; }
    void re(double& x) { string t; re(t); x = stod(t); }
    void re(ld& x) { string t; re(t); x = stold(t); }
    template<class T, class... Ts> void re(T& t, Ts&... ts) { 
        re(t); re(ts...); 
    }

    template<class T> void re(complex<T>& x) { T a,b; re(a,b); x = cd(a,b); }
    template<class T1, class T2> void re(pair<T1,T2>& p) { re(p.f,p.s); }
    template<class T> void re(vector<T>& a) { fax(i,sz(a)) re(a[i]); }
    template<class T, size_t SZ> void re(array<T,SZ>& a) { fax(i,SZ) re(a[i]); }
}

using namespace input;

namespace output {
    void pr(int x) { cout << x; }
    void pr(long x) { cout << x; }
    void pr(ll x) { cout << x; }
    void pr(unsigned x) { cout << x; }
    void pr(unsigned long x) { cout << x; }
    void pr(unsigned long long x) { cout << x; }
    void pr(float x) { cout << x; }
    void pr(double x) { cout << x; }
    void pr(ld x) { cout << x; }
    void pr(char x) { cout << x; }
    void pr(const char* x) { cout << x; }
    void pr(const string& x) { cout << x; }
    void pr(bool x) { pr(x ? "true" : "false"); }
    
    template<class T1, class T2> void pr(const pair<T1,T2>& x);
    template<class T> void pr(const T& x);
    
    template<class T, class... Ts> void pr(const T& t, const Ts&... ts) { 
        pr(t); pr(ts...); 
    }
    template<class T1, class T2> void pr(const pair<T1,T2>& x) { 
        pr("{",x.f,", ",x.s,"}"); 
    }
    template<class T> void pr(const T& x) { 
        pr("{"); // const iterator needed for vector<bool>
        bool fst = 1; for (const auto& a: x) pr(!fst?", ":"",a), fst = 0; 
        pr("}");
    }
    
    void ps() { pr("\n"); } // print w/ spaces
    template<class T, class... Ts> void ps(const T& t, const Ts&... ts) { 
        pr(t); if (sizeof...(ts)) pr(" "); ps(ts...); 
    }
    
    void pc() { pr("]\n"); } // debug w/ commas
    template<class T, class... Ts> void pc(const T& t, const Ts&... ts) { 
        pr(t); if (sizeof...(ts)) pr(", "); pc(ts...); 
    }
    #define dbg(x...) pr("[",#x,"] = ["), pc(x);
}

using namespace output;

namespace io {
    void setIn(string s) { freopen(s.c_str(),"r",stdin); }
    void setOut(string s) { freopen(s.c_str(),"w",stdout); }
    void setIO(string s = "") {
        ios_base::sync_with_stdio(0); cin.tie(0); // fast I/O
        if (sz(s)) { setIn(s+".in"), setOut(s+".out"); } // for USACO
    }
}

using namespace io;

mt19937 rnd(chrono::high_resolution_clock::now().time_since_epoch().count());

const int MOD = 1000000007; // 998244353
const ll INF = 1e18;
const int MX = 200005;
const ld PI = 4*atan((ld)1);

BIT<int, MX> b; int N; bool done[MX]; queue<int> pos[MX+1][2];

void update(int l, int r, int x){
   l++; r++;
   b.upd(l, x);
   if(r < 2*N) {
      b.upd(r+1, -x);
   }
}

int qry(int i){
   i++;
   return b.query(1,i);
}

ll count_swaps(vi S) {
   setIO(); 
   N = sz(S)/2;
   vi a(2*N);
   vi pend(2*N);
   fax(i,2*N){
     a[i] = S[i]; 
     if(a[i] > 0) {
        pos[a[i]][0].push(i);
     }
     else {
        pos[-a[i]][1].push(i);
     }
   } 
   ll ans = 0;
   fax(i,2*N){
     if(done[i]){
      update(i,2*N-1,pend[i]);
      continue;
     }
     int nxt = -1; 
     int dist = -1;
     if(a[i] > 0){
      nxt = pos[a[i]][1].front(); 
      pos[a[i]][1].pop();
      pos[a[i]][0].pop();
      dist = (nxt-i)-qry(nxt);
     }
     else{
      nxt = pos[-a[i]][0].front();
      pos[abs(a[i])][0].pop();
      pos[abs(a[i])][1].pop();
      dist = (nxt-i-1)-qry(nxt);
     }
     ans += dist;
     update(nxt,2*N-1,1);
     update(i,2*N-1,pend[i]);
     pend[nxt]--;
     done[nxt] = true;
   }
   pr(ans, "\n");
}

Compilation message (stderr)

shoes.cpp: In function 'll count_swaps(vi)':
shoes.cpp:206:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
shoes.cpp: In function 'void io::setIn(std::__cxx11::string)':
shoes.cpp:133:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
     void setIn(string s) { freopen(s.c_str(),"r",stdin); }
                            ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
shoes.cpp: In function 'void io::setOut(std::__cxx11::string)':
shoes.cpp:134:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
     void setOut(string s) { freopen(s.c_str(),"w",stdout); }
                             ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 10
• Subtask 2: 0 / 20
• Subtask 3: 0 / 20
• Subtask 4: 0 / 15
• Subtask 5: 0 / 20
• Subtask 6: 0 / 15