Submission #1274012

#	Time	Username	Problem	Language	Result	Execution time	Memory
1274012		nanaseyuzuki	JJOOII 2 (JOI20_ho_t2)	C++20	100 / 100	25 ms	5392 KiB

ho_t2

#include <bits/stdc++.h>
// Author: Kazuki_Will_Win_VOI_8703
#define fi first
#define se second
#define pii pair<int, int>
#define int long long
#define all(a) a.begin(), a.end()
using namespace std;

const int mn = 2e5 + 5, bm = (1 << 11) + 1, mod = 1e9 + 7, offset = 5e4, B = 320 + 5;
const int inf = 1e18, base = 311;

string s;
int n, k, prefix[3][mn];

int right_min(int Megumi, int st){
    int l = st, r = n, ans = -1;
    while(l <= r){
        int mid = (l + r) >> 1;
        if(prefix[Megumi][mid] - prefix[Megumi][st - 1] >= k){
            r = mid - 1;
            ans = mid;
        }
        else{
            l = mid + 1;
        }
    }
    return ans;
}

void solve(){
    cin >> n >> k >> s;
    s = "#" + s;

    for(int i = 1; i <= n; i++){
        int add0 = 0, add1 = 0, add2 = 0;
        if(s[i] == 'J') add0 ++;
        if(s[i] == 'O') add1 ++;
        if(s[i] == 'I') add2 ++;
        prefix[0][i] = prefix[0][i - 1] + add0;
        prefix[1][i] = prefix[1][i - 1] + add1;
        prefix[2][i] = prefix[2][i - 1] + add2;
    }
    int res = inf;
    for(int i = 1; i <= n; i++){
        int l = i, r, cur = i, nxt;
        //
        nxt = right_min(0, cur);
        if(nxt == -1) continue;
        cur = nxt + 1;

        nxt = right_min(1, cur);
        if(nxt == -1) continue;
        cur = nxt + 1;

        nxt = right_min(2, cur);
        if(nxt == -1) continue;
        r = nxt;

        res = min(res, r - l + 1 - 3 * k);
    }
    if(res == inf) res = -1;
    cout << res << '\n';
}

signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    int t = 1;
    // cin >> t;
    while(t--){
        solve();
    }
}

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