Submission #596413

#	Time	Username	Problem	Language	Result	Execution time	Memory
596413		thezomb1e	Street Lamps (APIO19_street_lamps)	C++17	40 / 100	5080 ms	18832 KiB

street_lamps

//thatsramen

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

#define eb emplace_back
#define pb push_back
#define ft first
#define sd second
#define pi pair<int, int>
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define dbg(...) dbg_out(__VA_ARGS__)

using ll = long long;
using ld = long double;
using namespace std;
using namespace __gnu_pbds;

//Constants
const ll INF = 5 * 1e18;
const int IINF = 2 * 1e9;
const ll MOD = 1e9 + 7;
// const ll MOD = 998244353;
const ll dx[4] = {1, 0, -1, 0}, dy[4] = {0, 1, 0, -1};
const ld PI = 3.14159265359;

//Templates
template<typename A, typename B> ostream& operator<<(ostream &os, const pair<A, B> &p) {return os << '(' << p.first << ", " << p.second << ')';}
template<typename T_container, typename T = typename enable_if<!is_same<T_container, string>::value, typename T_container::value_type>::type> ostream& operator<<(ostream &os, const T_container &v) {os << '['; string sep; for (const T &x : v) os << sep << x, sep = ", "; return os << ']';}
void dbg_out() {cerr << endl;}
template<typename Head, typename... Tail> void dbg_out(Head H, Tail... T) { cerr << H << ' '; dbg_out(T...); }
template<typename T> void mins(T& x, T y) {x = min(x, y);}
template<typename T> void maxs(T& x, T y) {x = max(x, y);}
template<typename T> using oset = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template<typename T> using omset = tree<T, null_type, less_equal<T>, rb_tree_tag, tree_order_statistics_node_update>;

//order_of_key(k): number of elements strictly less than k
//find_by_order(k): k-th element in the set

void setPrec() {cout << fixed << setprecision(15);}
void unsyncIO() {cin.tie(0)->sync_with_stdio(0);}
void setIn(string s) {freopen(s.c_str(), "r", stdin);}
void setOut(string s) {freopen(s.c_str(), "w", stdout);}
void setIO(string s = "") {
    unsyncIO(); setPrec();
    if(s.size()) setIn(s + ".in"), setOut(s + ".out");
}

// #define TEST_CASES

struct SegmentTree {

    vector<int> tre;
    int sz;

    SegmentTree(int n) {
        sz = 1;
        while (sz < n) sz *= 2;
        tre.assign(2 * sz, IINF);
        //build(a, 1, 0, sz);
    }

    void rcl(int x) {
        tre[x] = max(tre[2 * x], tre[2 * x + 1]);
    }

    void build(vector<int> &a, int x, int lx, int rx) {
        if (rx - lx == 1) {
            if (lx < a.size()) {
                tre[x] = a[lx];
            }
            return;
        }
        int m = (lx + rx) / 2;
        build(a, 2 * x, lx, m);
        build(a, 2 * x + 1, m, rx);
        rcl(x);
    }

    void set(int i, int v, int x, int lx, int rx) {
        if (rx - lx == 1) {
            tre[x] = v;
            return;
        }
        int m = (lx + rx) / 2;
        if (i < m) {
            set(i, v, 2 * x, lx, m);
        } else {
            set(i, v, 2 * x + 1, m, rx);
        }
        rcl(x);
    }

    void set(int i, int v) {
        set(i, v, 1, 0, sz);
    }

    int get(int l, int r, int x, int lx, int rx) {
        if (rx <= l || lx >= r) {
            return -IINF;
        }
        if (l <= lx && r >= rx) {
            return tre[x];
        }
        int m = (lx + rx) / 2;
        int s1 = get(l, r, 2 * x, lx, m);
        int s2 = get(l, r, 2 * x + 1, m, rx);
        return max(s1, s2);
    }

    int get(int l, int r) {
        return get(l, r, 1, 0, sz);
    }
};

struct BIT {
    vector<int> tre;
    int sz;
    BIT(int n) {
        sz = n;
        tre.assign(sz + 5, 0);
    }
    void upd(int i, int k) {
        while (i <= sz) {
            tre[i] += k;
            i += i & -i;
        }
    }
    int get(int i) {
        int res = 0;
        while (i > 0) {
            res += tre[i];
            i -= i & -i;
        }
        return res;
    }
    int get(int l, int r) {
        if (l > r) return 0;
        return get(r) - get(l - 1);
    }
};

void solve() {
    int n, q;
    cin >> n >> q;
    string s;
    cin >> s;
    string tmp = s;
    SegmentTree st(n);
    for (int i = 0; i < n; i++) {
        if (tmp[i] == '1') st.set(i, 0);
    }
    vector<tuple<int, int, int>> qs(q);
    bool subtask3 = true, subtask2 = true;
    for (int i = 0; i < q; i++) {
        string op;
        cin >> op;
        if (op == "toggle") {
            int x; cin >> x; x--;
            if (tmp[x] == '1') subtask3 = false;
            tmp[x] = (tmp[x] == '1' ? '0' : '1');
            qs[i] = {1, x, -1};
        } else {
            int l, r; cin >> l >> r;
            l--; r--;
            if (r - l != 1) subtask2 = false;
            qs[i] = {2, l, r};
        }
    }
    if (subtask2) {
        vector<int> last(n, -1), ans(n, 0);
        for (int i = 0; i < n; i++) {
            if (s[i] == '1') last[i] = 0;
        }
        for (int tim = 1; tim <= q; tim++) {
            auto [op, l, r] = qs[tim - 1];
            if (op == 1) {
                if (s[l] == '1') {
                    ans[l] += tim - last[l];
                    s[l] = '0';
                } else {
                    last[l] = tim;
                    s[l] = '1';
                }
            } else {
                int res = ans[l];
                if (s[l] == '1') {
                    res += tim - last[l];
                }
                cout << res << '\n';
            }
        }
        return;
    }
    if (subtask3) {
         for (int tim = 1; tim <= q; tim++) {
            auto [op, l, r] = qs[tim - 1];
            if (op == 1) {
                st.set(l, tim);
            } else {
                int mx = st.get(l, r);
                mins(mx, tim);
                cout << tim - mx << '\n';
            }
        }
        return;
    }
    BIT bit(n);
    vector<vector<int>> ans(n, vector<int> (n, 0));
    for (int tim = 1; tim <= q; tim++) {
        auto [op, l, r] = qs[tim - 1];
        if (op == 1) {
            if (s[l] == '1') {
                bit.upd(l, -1);
                s[l] = '0';
            } else {
                bit.upd(l, 1);
                s[l] = '1';
            }
        } else {
            cout << ans[l][r] << '\n';
        }
        for (int i = 0; i < n; i++) {
            for (int j = i + 1; j < n; j++) {
                if (bit.get(i, j) == j - i + 1) {
                    ans[i][j]++;
                }
            }
        }
    }
}

int main() {
    setIO();

    int tt = 1;
    #ifdef TEST_CASES
        cin >> tt;
    #endif

    while (tt--)
        solve();

    return 0;
}

Compilation message (stderr)

street_lamps.cpp: In member function 'void SegmentTree::build(std::vector<int>&, int, int, int)':
street_lamps.cpp:71:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   71 |             if (lx < a.size()) {
      |                 ~~~^~~~~~~~~~
street_lamps.cpp: In function 'void setIn(std::string)':
street_lamps.cpp:44:30: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   44 | void setIn(string s) {freopen(s.c_str(), "r", stdin);}
      |                       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
street_lamps.cpp: In function 'void setOut(std::string)':
street_lamps.cpp:45:31: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   45 | void setOut(string s) {freopen(s.c_str(), "w", stdout);}
      |                        ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

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