Submission #364237

#	Time	Username	Problem	Language	Result	Execution time	Memory
364237		Lam_lai_cuoc_doi	JJOOII 2 (JOI20_ho_t2)	C++17	100 / 100	10 ms	3764 KiB

ho_t2

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using ull = unsigned long long;

const bool typetest = 0;
const int N = 2e5 + 5;
const int Inf = 1e9 + 7;
int n, k;
string s;
int J[N], I[N];
vector<pair<int, int>> O;
vector<int> a;

void Read()
{
    cin >> n >> k;
    cin >> s;
    s = " " + s;
}

void Solve()
{
    fill_n(J, N, Inf);
    fill_n(I, N, Inf);
    for (int i = 1; i <= n; ++i)
    {
        J[i] = min(J[i], J[i - 1] + 1);
        if (s[i] == 'J')
        {
            a.push_back(i);
            if (a.size() >= k)
                J[i] = min(J[i], i - a[a.size() - k] + 1 - k);
        }
    }
    a.clear();
    for (int i = n; i; --i)
    {
        I[i] = min(I[i], I[i + 1] + 1);
        if (s[i] == 'I')
        {
            a.push_back(i);
            if (a.size() >= k)
                I[i] = min(I[i], a[a.size() - k] - i + 1 - k);
        }
    }
    a.clear();
    for (int i = 1; i <= n; ++i)
        if (s[i] == 'O')
        {
            a.push_back(i);
            if (a.size() >= k)
                O.push_back({a[a.size() - k], i});
        }
    int ans(Inf);
    for (auto i : O)
        ans = min(ans, J[i.first - 1] + i.second - i.first + 1 - k + I[i.second + 1]);
    cout << (ans == Inf ? -1 : ans);
}

int32_t main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int t(1);
    if (typetest)
        cin >> t;
    for (int _ = 1; _ <= t; ++_)
    {
        Read();
        Solve();
    }
}

Compilation message (stderr)

ho_t2.cpp: In function 'void Solve()':
ho_t2.cpp:33:26: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   33 |             if (a.size() >= k)
      |                 ~~~~~~~~~^~~~
ho_t2.cpp:44:26: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   44 |             if (a.size() >= k)
      |                 ~~~~~~~~~^~~~
ho_t2.cpp:53:26: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   53 |             if (a.size() >= k)
      |                 ~~~~~~~~~^~~~

• Subtask 1: 1 / 1
• Subtask 2: 12 / 12
• Subtask 3: 87 / 87