Submission #93700

#	Time	Username	Problem	Language	Result	Execution time	Memory
93700		rkocharyan	Election (BOI18_election)	C++14	0 / 100	7 ms	504 KiB

election

#include <bits/stdc++.h>

using namespace std;

const int N = 5e5 + 7;
const int inf = 1e5 + 7;

struct node {
    int val, lazy;
} pref[4 * N], suf[4 * N];

void push(int v, int tl, int tr) {
    if(pref[v].lazy) {
        pref[v].val += pref[v].lazy;
        if(tl != tr) {
            pref[2 * v + 1].lazy += pref[v].lazy;
            pref[2 * v + 2].lazy += pref[v].lazy;
        }
        pref[v].lazy = 0;
    }
}

void update(int v, int tl, int tr, int l, int r, int val) {
    push(v, tl, tr);
    if(l > r) return;
    if(tl == l && tr == r) {
        pref[v].lazy = val;
        push(v, tl, tr);
        return;
    }
    int tm = (tl + tr) / 2;
    update(2 * v + 1, tl, tm, l, min(r, tm), val);
    update(2 * v + 2, tm + 1, tr, max(l, tm + 1), r, val);
    pref[v].val = min(pref[2 * v + 1].val, pref[2 * v + 2].val);
}

int get(int v, int tl, int tr, int l, int r) {
    push(v, tl, tr);
    if(l > r) return inf;
    if(tl == l && tr == r) {
        return pref[v].val;
    }
    int tm = (tl + tr) / 2;
    int gl = get(2 * v + 1, tl, tm, l, min(r, tm));
    int gr = get(2 * v + 2, tm + 1, tr, max(l, tm + 1), r);
    return min(gl, gr);
}

void push2(int v, int tl, int tr) {
    if(suf[v].lazy) {
        suf[v].val += suf[v].lazy;
        if(tl != tr) {
            suf[2 * v + 1].lazy += suf[v].lazy;
            suf[2 * v + 2].lazy += suf[v].lazy;
        }
        suf[v].lazy = 0;
    }
}

void update2(int v, int tl, int tr, int l, int r, int val) {
    push2(v, tl, tr);
    if(l > r) return;
    if(tl == l && tr == r) {
        suf[v].lazy = val;
        push2(v, tl, tr);
        return;
    }
    int tm = (tl + tr) / 2;
    update2(2 * v + 1, tl, tm, l, min(r, tm), val);
    update2(2 * v + 2, tm + 1, tr, max(l, tm + 1), r, val);
    suf[v].val = min(suf[2 * v + 1].val, suf[2 * v + 2].val);
}

int get2(int v, int tl, int tr, int l, int r) {
    push2(v, tl, tr);
    if(l > r) return inf;
    if(tl == l && tr == r) {
        return suf[v].val;
    }
    int tm = (tl + tr) / 2;
    int gl = get2(2 * v + 1, tl, tm, l, min(r, tm));
    int gr = get2(2 * v + 2, tm + 1, tr, max(l, tm + 1), r);
    return min(gl, gr);
}

int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    int n;
    cin >> n;
    string s;
    cin >> s;
    vector <int> pf(n + 1, 0), sf(n + 2, 0);
    for(int i = 0; i < n; i++) {
        pf[i + 1] = s[i] == 'C' ? 1 : -1;
        pf[i + 1] += pf[i];
        update(0, 1, n, i + 1, i + 1, pf[i + 1]);
    }
    for(int i = n - 1; i >= 0; i--) {
        sf[i + 1] = s[i] == 'C' ? 1 : -1;
        sf[i + 1] += sf[i + 2];
        update2(0, 1, n, i + 1, i + 1, sf[i + 1]);
    }
    int q;
    cin >> q;
    for(int i = 0; i < q; i++) {
        int l, r;
        cin >> l >> r;
        update(0, 1, n, l, r, -pf[l - 1]);
        update2(0, 1, n, l, r, -sf[r + 1]);
        int g1 = -get(0, 1, n, l, r);
        int g2 = -get2(0, 1, n, l, r);
        int ans = max(0, max(g1, g2));
        cout << ans << '\n';
        update(0, 1, n, l, r, pf[l - 1]);
        update2(0, 1, n, l, r, sf[r + 1]);
    }
    return 0;
}

• Subtask 1: 0 / 28
• Subtask 2: 0 / 54
• Subtask 3: 0 / 18