Submission #934390

#	Time	Username	Problem	Language	Result	Execution time	Memory
934390		VladaMG98	Street Lamps (APIO19_street_lamps)	C++17	60 / 100	449 ms	22968 KiB

street_lamps

// Problem: C - Street Lamps
// Contest: Virtual Judge - 2024-02-27 APIO Simulation
// URL: https://vjudge.net/contest/612540#problem/C
// Memory Limit: 512 MB
// Time Limit: 5000 ms
//
// Powered by CP Editor (https://cpeditor.org)

#include <bits/stdc++.h>
using namespace std;

#define rep(i, a, b) for(int i = a; i < (b); ++i)
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
#define print(A,t) cerr << #A << ": "; copy(all(A),ostream_iterator<t>(cerr," " )); cerr << endl
#define prArr(A,n,t)  cerr << #A << ": "; copy(A,A + n,ostream_iterator<t>(cerr," " )); cerr << endl
#define what_is(x) cerr << #x << " is " << x << endl
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef vector<int> vi;

const int MAXQ = 300010;
int n, q; string s;
int type[MAXQ], a[MAXQ], b[MAXQ];

void subtask1() {
    vector<vector<bool>> history;
    vector<bool> cur(n);
    rep(i, 0, n) cur[i] = (s[i] == '1');
    history.push_back(cur);

    rep (qq, 1, q + 1) {
        if (type[qq]) {
            int l = a[qq], r = b[qq];
            l -= 1; r -= 1;
            int ans = 0;
            for (auto ev : history) {
                int cnt = 0;
                rep(k, l, r) cnt += ev[k];
                if (cnt == r - l) ans += 1;
            }
            cout << ans << endl;
        } else {
            int pos = a[qq];
            pos -= 1;
            cur[pos] = !cur[pos];
        }
        history.push_back(cur);
    }
}

void subtask2() {
    vector<bool> cur(n);
    rep(i, 0, n) cur[i] = (s[i] == '1');

    vector<int> last_turned_on(n, 0);
    vector<int> ans(n, 0);
    int cur_time = 0;
    rep (qq, 1, q + 1) {
        cur_time += 1;
        if (type[qq]) {
            int l = a[qq], r = b[qq];
            l -= 1; r -= 1;
            // so we only care about l
            int ret = ans[l] + (cur[l] ? cur_time - last_turned_on[l] : 0);
            cout << ret << endl;
        } else {
            int pos = a[qq];
            pos -= 1;
            if (cur[pos]) {
                ans[pos] += (cur_time - last_turned_on[pos]);
                cur[pos] = false;
            } else {
                last_turned_on[pos] = cur_time;
                cur[pos] = true;
            }
        }
    }
}

int t[MAXQ << 1];
void build() {
    for (int i = n - 1; i > 0; --i) t[i] = max(t[i << 1], t[i << 1 | 1]);
}
void modify (int pos, int val) {
    for (t[pos += n] = val; pos > 1; pos >>= 1) t[pos >> 1] = max(t[pos], t[pos ^ 1]);
}
int query (int l, int r) {
    int ans = 0;
    for (l += n, r += n; l < r; l >>= 1, r >>= 1) {
        if (l & 1) ans = max(ans, t[l++]);
        if (r & 1) ans = max(ans, t[--r]);
    }
    return ans;
}
void subtask3() {
    for (int i = 0; i < n; i++) t[n + i] = INT_MAX;
    for (int i = 0; i < n; i++) {
        if (s[i] == '1') t[n + i] = 0;
    }

    build();
    int cur_time = 0;
    rep (qq, 1, q + 1) {
        cur_time += 1;
        if (type[qq]) {
            int l = a[qq] - 1, r = b[qq] - 1;
            int goes_on = query(l, r);
            if (goes_on >= cur_time) cout << 0 << endl;
            else cout << cur_time - goes_on << endl;
        } else {
            int pos = a[qq] - 1;
            modify(pos, cur_time);
        }
    }
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL); cout.tie(NULL);

    cin >> n >> q >> s;
    for (int i = 1; i <= q; i++) {
        string str; cin >> str;
        type[i] = (str == "query");
        if (type[i]) cin >> a[i] >> b[i];
        else cin >> a[i];
}

    if (n <= 100 && q <= 100) { subtask1(); return 0; }
    bool is_two = true;
    for (int i = 1; i <= q; i++) {
        if (type[i] && b[i] != a[i] + 1) {
            is_two = false;
            break;
        }
    }
    if (is_two) { subtask2(); return 0; }

    unordered_map<int, int> toggles;
    for (int i = 1; i <= q; i++) {
        if (!type[i]) toggles[a[i] - 1] += 1;
    }

    bool is_three = true;
    for (auto [k, v] : toggles) {
        if (v > 1) { is_three = false; break; }
        if (s[k] == '1') { is_three = false; break; }
    }

    if (is_three) { subtask3(); return 0; }
    return 0;
}

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