Submission #957692

#	Time	Username	Problem	Language	Result	Execution time	Memory
957692		BhavayGoyal	JJOOII 2 (JOI20_ho_t2)	C++14	100 / 100	25 ms	7312 KiB

ho_t2

#include <bits/stdc++.h>
using namespace std;

#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;

template<class T> using oset = 
            tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

#define ll long long
#define ld long double
#define ar array
#define vi vector<int>
#define vii vector<vector<int>>
#define pii pair<int, int>
#define pb push_back
#define all(x) x.begin(), x.end()
#define f first
#define s second
#define endl "\n"

const int MOD = 1e9+7;
const int inf = 1e9;
const ll linf = 1e18;

const int d4i[4]={-1, 0, 1, 0}, d4j[4]={0, 1, 0, -1};
const int d8i[8]={-1, -1, 0, 1, 1, 1, 0, -1}, d8j[8]={0, 1, 1, 1, 0, -1, -1, -1};

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());


// -------------------------------------------------- Main Code --------------------------------------------------

const int N = 2e5+5;
int arr[N];
vi pos[N];

void sol() {
    int n, k; cin >> n >> k;
    for (int i = 1; i <= n; i++) {
        char x; cin >> x; 
        if (x == 'J') arr[i] = 0;
        else if (x == 'O') arr[i] = 1;
        else arr[i] = 2;
        pos[arr[i]].pb(i);
    }

    auto get = [&](int ch, int idx) {
        if (idx == -1) return -1;
        int i = lower_bound(all(pos[ch]), idx) - pos[ch].begin();
        i += k-1;
        if (i >= pos[ch].size()) return -1;
        return pos[ch][i]+1;
    };

    int ans = inf;

    for (int i = 1; i <= n; i++) {
        int j = i;
        j = get(0, j);
        j = get(1, j);
        j = get(2, j);
        if (j == -1) break;
        int x = i-1 + n-j+1;
        ans = min(ans, n - x - k*3);
    }

    if (ans == inf) cout << -1 << endl;
    else cout << ans << endl;
}

int main () {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    int t = 1;
    // cin >> t; 
    while (t--) {
        sol();
    }
    return 0;
}

Compilation message (stderr)

ho_t2.cpp: In lambda function:
ho_t2.cpp:53:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   53 |         if (i >= pos[ch].size()) return -1;
      |             ~~^~~~~~~~~~~~~~~~~

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