Submission #1270717

#	Time	Username	Problem	Language	Result	Execution time	Memory
1270717		hainam2k9	Railway Trip 2 (JOI22_ho_t4)	C++20	100 / 100	517 ms	70968 KiB

Main

#include <bits/stdc++.h>
#define tt cin.tie(0), cout.tie(0), ios_base::sync_with_stdio(0)
#define fo freopen((NAME+".INP").c_str(), "r", stdin), freopen((NAME+".OUT").c_str(), "w", stdout)
#define ll long long
#define ull unsigned long long
#define i128 __int128
#define db long double
#define sz(a) ((int)(a).size())
#define pb emplace_back
#define pf emplace_front
#define pob pop_back
#define pof pop_front
#define lb lower_bound
#define ub upper_bound
#define fi first
#define se second
#define ins emplace
#define mp make_pair
using namespace std;
const int MOD = 1e9+7, MAXN = 1e5+5, lim = 18;
const string NAME = "";
inline pair<int,int> combine(const pair<int,int>& a, const pair<int,int>& b){
    return {min(a.fi,b.fi),max(a.se,b.se)};
}
struct SegmentTree{
    pair<int,int> sgt[MAXN<<2];
    void build(int id, int l, int r, pair<int,int> p[]){
        if(l==r) return sgt[id]=p[l], void();
        int mid=(l+r)>>1;
        build(id<<1,l,mid,p);
        build(id<<1|1,mid+1,r,p);
        sgt[id]=combine(sgt[id<<1],sgt[id<<1|1]);
    }
    pair<int,int> get(int id, int l, int r, int u, int v){
        if(v<l||r<u) return {1e9,0};
        if(u<=l&&r<=v) return sgt[id];
        int mid=(l+r)>>1;
        return combine(get(id<<1,l,mid,u,v),get(id<<1|1,mid+1,r,u,v));
    }
}ST[20];
int n,k,m,q;
pair<int,int> st[20][MAXN];
vector<int> upd[MAXN],upd2[MAXN];
void init(){
    multiset<int> ms;
    for(int i = 1; i<=n; ++i){
        for(int& j : upd[i]){
            if(j>0) ms.ins(j);
            else ms.erase(ms.find(-j));
        }
        st[0][i].se=(ms.empty() ? i : *ms.rbegin());
    }
    ms.clear();
    for(int i = n; i>0; --i){
        for(int& j : upd2[i]){
            if(j>0) ms.ins(j);
            else ms.erase(ms.find(-j));
        }
        st[0][i].fi=(ms.empty() ? i : *ms.begin());
    }
    ST[0].build(1,1,n,st[0]);
}
int main()
{
    tt;
    if(fopen((NAME + ".INP").c_str(), "r")) fo;
    cin >> n >> k >> m;
    for(int i = 1; i<=m; ++i){
        int x,y;
        cin >> x >> y;
        if(x<y) upd[x].pb(y), upd[min(x+k,y)].pb(-y);
        else upd2[x].pb(y), upd2[max(x-k,y)].pb(-y);
    }
    init();
    for(int i = 1; i<=lim; ++i){
        for(int j = 1; j<=n; ++j)
            st[i][j]=ST[i-1].get(1,1,n,st[i-1][j].fi,st[i-1][j].se);
        ST[i].build(1,1,n,st[i]);
    }
    cin >> q;
    while(q--){
        int x,y,rs=0;
        cin >> x >> y;
        int l=x,r=x;
        if(x<y){
            if(ST[lim].get(1,1,n,l,r).se>=y){
                for(int i = lim; i>=0; --i){
                    pair<int,int> p = ST[i].get(1,1,n,l,r);
                    if(p.se<y) rs+=1<<i, l=p.fi, r=p.se;
                }
            }else rs=-2;
        }else{
            if(ST[lim].get(1,1,n,l,r).fi<=y){
                for(int i = lim; i>=0; --i){
                    pair<int,int> p = ST[i].get(1,1,n,l,r);
                    if(p.fi>y) rs+=1<<i, l=p.fi, r=p.se;
                }
            }else rs=-2;
        }
        cout << rs+1 << "\n";
    }
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:3:19: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    3 | #define fo freopen((NAME+".INP").c_str(), "r", stdin), freopen((NAME+".OUT").c_str(), "w", stdout)
      |            ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:66:45: note: in expansion of macro 'fo'
   66 |     if(fopen((NAME + ".INP").c_str(), "r")) fo;
      |                                             ^~
Main.cpp:3:63: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    3 | #define fo freopen((NAME+".INP").c_str(), "r", stdin), freopen((NAME+".OUT").c_str(), "w", stdout)
      |                                                        ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:66:45: note: in expansion of macro 'fo'
   66 |     if(fopen((NAME + ".INP").c_str(), "r")) fo;
      |                                             ^~

• Subtask 1: 8 / 8
• Subtask 2: 8 / 8
• Subtask 3: 11 / 11
• Subtask 4: 25 / 25
• Subtask 5: 35 / 35
• Subtask 6: 13 / 13