Submission #1261453

#	Time	Username	Problem	Language	Result	Execution time	Memory
1261453		hoa208	JJOOII 2 (JOI20_ho_t2)	C++20	100 / 100	6 ms	6928 KiB

ho_t2

#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define FOR(i, a, b) for (int i = (a), _b = (b); i <= _b; i++)
#define FORD(i, b, a) for (int i = (b), _a = (a); i >= _a; i--)
#define pa pair<ll, ll>
#define fi first
#define se second
#define bit(mask, j) ((mask >> j) & 1)
#define t_test int t;cin >> t;while(t--)
const   ll mod = 1e9 + 7;
const   ll INF = 1e18;
inline  void adm(ll &x){if(x>=mod)x%=mod;else if(x<0)x+=mod;}
//--------------------------------------------------------------------

string t = "JOI";
const ll N = 2e5 + 10;
ll nxt[N][3], cnt[3], L[3], c[N];
void hbmt() {
    ll n, k;
    cin >> n >> k;
    string s;
    cin >> s;
    s = ' ' + s;
    FOR(j, 0, 2) nxt[n + 1][j] = n + 1;
    FORD(i, n, 0) {
       FOR(j, 0, 2) nxt[i][j] = nxt[i + 1][j];
       if(i != 0)
        nxt[i][t.find(s[i])] = i; 
    }
    FOR(i, 1, n) {
        ll kt = t.find(s[i]);
        cnt[kt]++;
        if(cnt[kt] >= k) {
            L[kt] = nxt[L[kt] + 1][kt];
            c[L[kt]] = i;
        }
    }
    ll ans = INF;
    FOR(i, 1, n) {
        if(c[i] && s[i] == 'J') {
            if(c[nxt[c[i]][1]]) {
                if(c[nxt[c[nxt[c[i]][1]]][2]]) {
                    ans = min(ans, c[nxt[c[nxt[c[i]][1]]][2]] - i + 1 - 3 * k);
                }
            }
        }
    }
    if(ans == INF) cout << -1;
    else cout << ans;
}

int main() {
    
    ios_base::sync_with_stdio(0);
    cin.tie(0);cout.tie(0);
    
    if(fopen("hbmt.inp", "r")) {
        freopen("hbmt.inp", "r", stdin);
        freopen("hbmt.out", "w", stdout);
    }
    
    // t_test 
    hbmt();
    return 0;
}

Compilation message (stderr)

ho_t2.cpp: In function 'int main()':
ho_t2.cpp:59:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   59 |         freopen("hbmt.inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
ho_t2.cpp:60:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   60 |         freopen("hbmt.out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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