oj.uz

Submission #379301

# Submission time Handle Problem Language Result Execution time Memory
379301 2021-03-17T23:38:33 Z thecodingwizard Election (BOI18_election) C++11
100 / 100
 1804 ms 30324 KB 
#include <bits/stdc++.h>

using namespace std;

using ll = long long;
#define ii pair<int, int>
#define f first
#define s second
#define pb push_back
#define mp make_pair
#define all(x) x.begin(), x.end()
#define sz(x) (int)x.size()
#define F0R(i, n) for (int i = 0; i < n; i++)
#define FOR(i, a, b) for (int i = a; i < b; i++)
#define inf 1000000010

#define maxn 500010

int ans[maxn];
int maxPrefix[4*maxn], sum[4*maxn];

// first is sum, second is max prefix
ii qry(int p, int i, int j, int L, int R) {
    if (i > R || j < L) return mp(0, -inf);
    if (L <= i && j <= R) {
        return mp(sum[p], maxPrefix[p]);
    }
    ii lft = qry(p*2, i, (i+j)/2, L, R);
    ii rht = qry(p*2+1, (i+j)/2+1, j, L, R);
    return mp(lft.f + rht.f, max(lft.s, lft.f + rht.s));
}

void upd(int p, int i, int j, int k, int v) {
    if (i > k || j < k) return;
    if (i == j && j == k) {
        maxPrefix[p] = v;
        sum[p] = v;
        return;
    }
    upd(p*2, i, (i+j)/2, k, v);
    upd(p*2+1, (i+j)/2+1, j, k, v);
    maxPrefix[p] = max(maxPrefix[p*2], sum[p*2]+maxPrefix[p*2+1]);
    sum[p] = sum[p*2]+sum[p*2+1];
}

int bit[maxn];

int get(int k) {
    int s = 0;
    while (k) {
        s += bit[k];
        k -= k&-k;
    }
    return s;
}
void add(int k, int v) {
    while (k < maxn) {
        bit[k] += v;
        k += k&-k;
    }
}

int main() {
    cin.tie(0)->sync_with_stdio(0);

    int n; cin >> n;
    string s; cin >> s; s = " " + s;

    int q; cin >> q;
    vector<pair<ii, int>> queries;

    F0R(i, q) {
        int l, r; cin >> l >> r;
        queries.pb(mp(mp(l, r), i));
    }
    sort(all(queries), [](pair<ii, int> a, pair<ii, int> b) { return a.f.s < b.f.s; });

    int idx = 0;
    stack<int> removedT;
    for (int i = 1; i <= n; i++) {
        if (s[i] == 'C') {
            upd(1, 1, n, i, -1);
            if (!removedT.empty()) {
                int tgt = removedT.top();
                add(tgt, -1);
                upd(1, 1, n, tgt, 1);
                removedT.pop();
            }
        } else {
            removedT.push(i);
            add(i, 1);
        }
        
        while (idx < q && queries[idx].f.s == i) {
            // process query idx
            int toRemove = get(queries[idx].f.s) - get(queries[idx].f.f-1);

            int extraRemove = qry(1, 1, n, queries[idx].f.f, queries[idx].f.s).s;

            ans[queries[idx].s] = toRemove + max(extraRemove, 0);
            idx++;
        }
    }

    F0R(i, q) cout << ans[i] << endl;

    return 0;
}

Subtask #1
28.0 / 28.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 492 KB Output is correct
2 Correct 6 ms 492 KB Output is correct
3 Correct 6 ms 492 KB Output is correct
4 Correct 6 ms 492 KB Output is correct
5 Correct 6 ms 492 KB Output is correct

Subtask #2
54.0 / 54.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 492 KB Output is correct
2 Correct 6 ms 492 KB Output is correct
3 Correct 6 ms 492 KB Output is correct
4 Correct 6 ms 492 KB Output is correct
5 Correct 6 ms 492 KB Output is correct
6 Correct 227 ms 5352 KB Output is correct
7 Correct 215 ms 5212 KB Output is correct
8 Correct 217 ms 5232 KB Output is correct
9 Correct 222 ms 5212 KB Output is correct
10 Correct 219 ms 5212 KB Output is correct
11 Correct 219 ms 5332 KB Output is correct
12 Correct 219 ms 5340 KB Output is correct
13 Correct 213 ms 4976 KB Output is correct
14 Correct 222 ms 5212 KB Output is correct
15 Correct 217 ms 5340 KB Output is correct

Subtask #3
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 492 KB Output is correct
2 Correct 6 ms 492 KB Output is correct
3 Correct 6 ms 492 KB Output is correct
4 Correct 6 ms 492 KB Output is correct
5 Correct 6 ms 492 KB Output is correct
6 Correct 227 ms 5352 KB Output is correct
7 Correct 215 ms 5212 KB Output is correct
8 Correct 217 ms 5232 KB Output is correct
9 Correct 222 ms 5212 KB Output is correct
10 Correct 219 ms 5212 KB Output is correct
11 Correct 219 ms 5332 KB Output is correct
12 Correct 219 ms 5340 KB Output is correct
13 Correct 213 ms 4976 KB Output is correct
14 Correct 222 ms 5212 KB Output is correct
15 Correct 217 ms 5340 KB Output is correct
16 Correct 1753 ms 29412 KB Output is correct
17 Correct 1671 ms 29056 KB Output is correct
18 Correct 1755 ms 29356 KB Output is correct
19 Correct 1628 ms 28652 KB Output is correct
20 Correct 1790 ms 28504 KB Output is correct
21 Correct 1726 ms 30324 KB Output is correct
22 Correct 1742 ms 29196 KB Output is correct
23 Correct 1676 ms 27972 KB Output is correct
24 Correct 1749 ms 29072 KB Output is correct
25 Correct 1804 ms 28284 KB Output is correct