Submission #1234290

#	Time	Username	Problem	Language	Result	Execution time	Memory
1234290		dssfsuper2	Street Lamps (APIO19_street_lamps)	C++20	40 / 100	233 ms	25984 KiB

street_lamps

#include <bits/stdc++.h>
using namespace std;
struct segtree{
    vector<int> st;
    int n;
    segtree(int N){
        n=N;
        st.assign(4*N, 1e9);
    }
    void build(int node, int left, int right, vector<int>&a){
        if(left==right){
            st[node]=a[left];
            return;
        }
        build(node*2, left, (left+right)/2, a);
        build(node*2+1, (left+right)/2+1, right, a);
    }
    void set(int node, int left, int right, int pos, int val){
        if(left==right && left==pos){
            st[node]=val;
            return;
        }
        if(right<pos || left>pos)return;
        set(node*2, left, (left+right)/2, pos, val);
        set(node*2+1, (left+right)/2+1, right, pos, val);
        st[node]=max(st[node*2], st[node*2+1]);
    }
    int query(int node, int left, int right, int ql, int qr){
        if(right<ql || left>qr){
            return -1e9;
        }
        if(left>=ql && right<=qr)return st[node];
        return max(query(node*2, left, (left+right)/2, ql, qr), query(node*2+1, (left+right)/2+1, right, ql, qr));
    }
};
signed main(){
    int n, q;cin>>n>>q;
    string s;cin>>s;
    vector<int> a;
    for(int i = 0;i<n;i++){
        if(s[i]=='1')a.push_back(1);
        else a.push_back(0);
    }

    vector<vector<int>> events;
    bool isss2=true;
    bool isss3=true;
    vector<int> statee=a;
    for(int i = 0;i<q;i++){
        string ev;cin>>ev;
        if(ev=="toggle"){
            int x;cin>>x;
            events.push_back({0, x});
            statee[x]^=1;
            if(statee[x]==0)isss3=false;
        }
        else{
            
            int x, y;cin>>x>>y;
            if(y-x!=1)isss2=false;
            events.push_back({1, x, y});
        }
    }
    if(isss3){
        segtree st(n);
        for(int i = 0;i<n;i++)if(a[i]==1)st.set(1, 0, n-1, i, -1);
        for(int i = 0;i<q;i++){
            if(events[i][0]==0){
                st.set(1, 0, n-1, events[i][1]-1, i);
            }
            else{
                cout << max(0, i-st.query(1, 0, n-1, events[i][1]-1, events[i][2]-2)) << '\n';
            }
        }
        return 0;
    }
    //now codes the ss2
    //segtree for max activation time, like it changes after each thing
    //like at first its infinity for all of them, then I set someone to one, two three etc
    //a query will just be the i-max, low bar 0
    if(isss2){
        vector<int> count=a;
        vector<int> state=a;
        vector<int> lastc(n, 0);
        for(int i = 0;i<q;i++){
            auto thing = events[i];
            if(thing[0]==0){
                if(state[thing[1]-1]==1)count[thing[1]-1]+=(i-lastc[thing[1]-1]);
                state[thing[1]-1]^=1;
            
                lastc[thing[1]-1]=i;
            }
            else{
                int res = count[thing[1]-1];
                if(state[thing[1]-1]==1)res+=(i-lastc[thing[1]-1]);
                cout << res << '\n';
            }
        }
        return 0;
    }
    if(n<=200 && q<=200){
        vector<vector<int>> strings={a};
        for(auto thing:events){
            if (thing[0]==0){
                a[thing[1]-1]^=1;
            }
            else{
                int tres = 0;
                for(auto strin:strings){
                    bool res = true;

                    for(int i =thing[1]-1;i<thing[2]-1;i++){
                        if(strin[i]==0)res=false;
                    }
                    if(res)tres++;
                }
                cout << tres << '\n';
            }
            strings.push_back(a);
        }
    }
}

• Subtask 1: 20 / 20
• Subtask 2: 20 / 20
• Subtask 3: 0 / 20
• Subtask 4: 0 / 20
• Subtask 5: 0 / 20