Submission #1279213

#	Time	Username	Problem	Language	Result	Execution time	Memory
1279213		herominhsteve	Hedgehog Daniyar and Algorithms (IZhO19_sortbooks)	C++20	100 / 100	802 ms	80880 KiB

sortbooks

#include <bits/stdc++.h>
#define el '\n'
#define FNAME "Library"
#define allof(x) x.begin(),x.end()
#define allof1(x) x.begin()+1,x.end()
#define mset(x,n) memset(x,(n),sizeof(x))
using namespace std;
const long long MOD = (long long)1e9 + 7;
template<class X,class Y> bool minimize(X &a,Y b){ if(a>b){a=b;return true;}return false;}
template<class X,class Y> bool maximize(X &a,Y b){ if(a<b){a=b;return true;}return false;}

void setup(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);cout.tie(0);
    if(fopen(FNAME".inp","r")){
        freopen(FNAME".inp","r",stdin);
        freopen(FNAME".out","w",stdout);
    }
}

using ll = long long;
const ll NEG = -(1LL<<60);

struct Query{
    int l,r;
    ll k;
    int id;
};

int n,q;
vector<ll> a;
vector<int> prevGreater;
vector<ll> pairVal; 

struct SegmentTree{
    int n;
    vector<ll> st;
    SegmentTree(): n(0) {}
    SegmentTree(int N){init(N);}
    
    void init(int N){
        n = N;
        st.assign(4*N+5, NEG);
    }

    void update(int node,int l,int r,int pos,ll val){
        if(l==r){
            st[node] = max(st[node],val);
            return;
        }
        int mid=(l+r)>>1;
        if(pos<=mid) update(node<<1,l,mid,pos,val);
        else update(node<<1|1,mid+1,r,pos,val);
        st[node] = max(st[node<<1],st[node<<1|1]);
    }

    void point_update_max(int pos,ll val){
        update(1,1,n,pos,val);
    }

    ll query(int node,int l,int r,int L,int R){
        if(R<l || r<L) return NEG;
        if(L<=l && r<=R) return st[node];
        int mid=(l+r)>>1;
        return max(query(node<<1,l,mid,L,R),
                   query(node<<1|1,mid+1,r,L,R));
    }

    ll range_max(int L,int R){
        if(L>R) return NEG;
        return query(1,1,n,L,R);
    }
} seg;

void init(){
    cin >> n >> q;
    a.assign(n+1,0);
    for(int i=1;i<=n;i++) cin >> a[i];

    prevGreater.assign(n+1,0);
    pairVal.assign(n+1,NEG);

    vector<int> st;
    st.reserve(n);
    for(int i=1;i<=n;i++){
        while(!st.empty() && a[st.back()] <= a[i]) st.pop_back();
        if(!st.empty()) prevGreater[i] = st.back();
        else prevGreater[i] = 0;
        st.push_back(i);
        if(prevGreater[i] > 0) pairVal[i] = a[i] + a[prevGreater[i]];
    }
}

void sol(){
    vector<Query> qs;
    qs.reserve(q);
    for(int i=0;i<q;i++){
        int l,r; ll k; cin >> l >> r >> k;
        qs.push_back({l,r,k,i});
    }

    sort(qs.begin(), qs.end(), [](const Query&A,const Query&B){
        if(A.r != B.r) return A.r < B.r;
        return A.l < B.l;
    });

    seg.init(n);
    vector<int> ans(q,0);
    int ptr=0;

    for(int r=1;r<=n;r++){
        if(prevGreater[r]>0){
            seg.point_update_max(prevGreater[r], pairVal[r]);
        }
        while(ptr<(int)qs.size() && qs[ptr].r==r){
            int L=qs[ptr].l;
            int R=qs[ptr].r;
            ll k=qs[ptr].k;
            int id=qs[ptr].id;

            ll mx=seg.range_max(L,R);
            if(mx==NEG) ans[id]=1;
            else ans[id]=(mx<=k)?1:0;
            ++ptr;
        }
    }

    for(int i=0;i<q;i++) cout << ans[i] << el;
}

int main(){
    setup();
    init();
    sol();
    return 0;
}

Compilation message (stderr)

sortbooks.cpp: In function 'void setup()':
sortbooks.cpp:16:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   16 |         freopen(FNAME".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
sortbooks.cpp:17:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   17 |         freopen(FNAME".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 8 / 8
• Subtask 2: 9 / 9
• Subtask 3: 13 / 13
• Subtask 4: 17 / 17
• Subtask 5: 30 / 30
• Subtask 6: 23 / 23