Submission #232784

#	Time	Username	Problem	Language	Result	Execution time	Memory
232784		Mercenary	Street Lamps (APIO19_street_lamps)	C++14	100 / 100	1391 ms	70532 KiB

street_lamps

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

#define pb push_back
#define mp make_pair
#define taskname "A"

using namespace std;
using namespace __gnu_pbds;

typedef long long ll;
typedef long double ld;
typedef pair<int,int> ii;
typedef tree <int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;

const int maxn = 3e5 + 5;
const int logn = log2(maxn) + 1;

struct BIT{
    vector<int> val, bit;
    BIT(){val.clear();bit.clear();}
    void init(){
        sort(val.begin(),val.end());
        val.erase(unique(val.begin(),val.end()),val.end());
        bit.resize(val.size() , 0);
    }
    void update(int x , int delta){
        for( ; x <= val.size() ; x += x & -x){
            bit[x - 1] += delta;
        }
    }
    void update_range(int l , int h , int delta){
        if(val.size() == 0)return;
        update(lower_bound(val.begin(),val.end(),l)-val.begin()+1 , delta);
        update(upper_bound(val.begin(),val.end(),h)-val.begin()+1, -delta);
    }
    int query(int x){
        int res = 0;
        for( x = upper_bound(val.begin(),val.end(),x)-val.begin() ; x > 0 ; x &= x - 1){
            res += bit[x - 1];
        }
        return res;
    }
}BIT2d[maxn];

int type[maxn] , a[maxn] , b[maxn];
bool state[maxn];
int n , q;

void fakeupdate(int a , int b){
    for( ; a > 0 ; a &= a - 1){
        BIT2d[a].val.pb(b);
    }
}

void update(int l , int h , int L , int H , int delta){
    for( ; l <= n ; l += l & -l){
        BIT2d[l].update_range(L,H,delta);
    }
    for(++h ; h <= n ; h += h & -h){
        BIT2d[h].update_range(L,H,-delta);
    }
}

int query(int a , int b){
    int res = 0;
    for( ; a > 0 ; a &= a - 1){
        res += BIT2d[a].query(b);
    }
    return res;
}

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    if(fopen(taskname".INP","r")){
		freopen(taskname".INP", "r",stdin);
		freopen(taskname".OUT", "w",stdout);
    }
    cin >> n >> q;
    string s;cin >> s;
    set<int> offset;offset.insert(n + 1);offset.insert(0);
    for(int i = 1 ; i <= n ; ++i){
        state[i] = (s[i - 1] == '1');
        if(!state[i])offset.insert(i);
    }
    for(int i = 1 ; i <= q ; ++i){
        cin >> s;
        if(s[0] == 'q'){
            type[i] = 0;
            cin >> a[i] >> b[i];
            fakeupdate(a[i],--b[i]);
        }else{
            type[i] = 1;
            cin >> a[i];
        }
    }
    for(int i = 1 ; i <= n ; ++i){
        BIT2d[i].init();
    }
    for(int i = 1 ; i <= q ; ++i){
        if(type[i] == 0){
            int res = query(a[i] , b[i]);
            auto it = offset.lower_bound(a[i]);
            if(*prev(it) < a[i] && (*it) > b[i])res += i;
            cout << res << '\n';
        }else{
            int x = a[i];
            if(state[x] == 0){//merge seq
                offset.erase(x);
                auto it = offset.lower_bound(x);
                update(*prev(it) + 1 , x , x, (*it) - 1 , -i);
            }else{//split seq
                auto it = offset.lower_bound(x);
                update(*prev(it) + 1 , x , x, (*it) - 1 , i);
//                cout << *prev(it) + 1 << " " << x << " " << (*it) - 1 << endl;
                offset.insert(x);
            }
            state[x] ^= 1;
        }
    }
}

Compilation message (stderr)

street_lamps.cpp: In member function 'void BIT::update(int, int)':
street_lamps.cpp:29:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for( ; x <= val.size() ; x += x & -x){
                ~~^~~~~~~~~~~~~
street_lamps.cpp: In function 'int main()':
street_lamps.cpp:79:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   freopen(taskname".INP", "r",stdin);
   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
street_lamps.cpp:80:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   freopen(taskname".OUT", "w",stdout);
   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

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