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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#543024#7689. Flipping Cardsmhw#TL 1ms3824kbC++231.3kb2024-09-01 12:53:142024-09-01 12:53:15

Judging History

你现在查看的是最新测评结果

  • [2024-09-01 12:53:15]
  • 评测
  • 测评结果:TL
  • 用时:1ms
  • 内存:3824kb
  • [2024-09-01 12:53:14]
  • 提交

answer

#include <bits/stdc++.h>
using namespace std;
using i64 = long long;
const i64 P = 998244353;
void solve() {
    int n;
    cin >> n;
    vector<pair<int, int>> a(n + 1);
    for (int i = 1; i <= n; i++) {
        cin >> a[i].first >> a[i].second;
    }
    auto check = [&](int x) -> bool {
        vector<int> b(n + 1);
        i64 ans = 0;
        for (int i = 1; i <= n; i++) {
            if (a[i].first >= x) ans++;
            if (a[i].first >= x && a[i].second < x) b[i] = -1;
            else if (a[i].first < x && a[i].second >= x) b[i] = 1;
        }
        vector<array<int, 2>> dp(n + 1);
        dp[0][0] = -1;
        int res = 0;
        for (int i = 1; i <= n; i++) {
            if (dp[i - 1][0] > 0) {
                dp[i][0] = dp[i - 1][0] + b[i];
                dp[i][1] = 1;
            } else {
                dp[i][0] = b[i];
                dp[i][1] = 0;
            }
            res = max(res, dp[i][0]);
        }
        return ans + res >= (n + 1) / 2;
    };
    int l = 0, r = 1e9;
    while (l < r) {
        int mid = (l + r) / 2;
        if (check(mid)) l = mid;
        else r = mid - 1;
    }
    cout << l << '\n';
}
int main() {
    ios::sync_with_stdio(0); cin.tie(0), cout.tie(0);
    int t = 1; 
    // cin >> t;
    while(t--) solve();
    return 0;
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 0ms
memory: 3592kb

input:

5
3 6
5 2
4 7
6 4
2 8

output:

6

result:

ok 1 number(s): "6"

Test #2:

score: 0
Accepted
time: 0ms
memory: 3824kb

input:

1
2 1

output:

2

result:

ok 1 number(s): "2"

Test #3:

score: 0
Accepted
time: 0ms
memory: 3592kb

input:

1
212055293 384338286

output:

384338286

result:

ok 1 number(s): "384338286"

Test #4:

score: 0
Accepted
time: 1ms
memory: 3588kb

input:

99
749159996 323524232
125448341 365892333
481980673 143665393
394405973 44741918
687549448 513811513
287088118 385131171
11865696 666468353
449920567 373650719
671547289 116780561
41003675 671513243
351534153 507850962
374160874 985661954
222519431 600582098
987220654 704142246
856147059 37783620
1...

output:

528957505

result:

ok 1 number(s): "528957505"

Test #5:

score: -100
Time Limit Exceeded

input:

101
1000000000 1000000000
1000000000 1000000000
1000000000 1000000000
1000000000 1000000000
1000000000 1000000000
1000000000 1000000000
1000000000 1000000000
1000000000 1000000000
1000000000 1000000000
1000000000 1000000000
1000000000 1000000000
1000000000 1000000000
1000000000 1000000000
1000000000...

output:


result: