Submission #536029

#	Time	Username	Problem	Language	Result	Execution time	Memory
536029		browntoad	JJOOII 2 (JOI20_ho_t2)	C++14	100 / 100	23 ms	10248 KiB

ho_t2

#include <bits/stdc++.h>
#pragma GCC optimize ("Ofast", "unroll-loops")
using namespace std;
#define ll long long
#define int ll
#define FOR(i,a,b) for (int i = (a); i<(b); i++)
#define REP(i,n) FOR(i,0,n)
#define REP1(i,n) FOR(i,1,n+1)
#define RREP(i,n) for (int i=(n)-1; i>=0; i--)
#define RREP1(i,n) for (int i=(n); i>=1; i--)
#define f first
#define s second
#define pb push_back
#define ALL(x) x.begin(),x.end()
#define SZ(x) (int)(x.size())
#define SQ(x) (x)*(x)
#define pii pair<int, int>
#define pdd pair<double ,double>
#define pcc pair<char, char> 
#define endl '\n'
//#define TOAD
#ifdef TOAD
#define bug(x) cerr<<__LINE__<<": "<<#x<<" is "<<x<<endl
#define IOS()
#else
#define bug(...)
#define IOS() ios::sync_with_stdio(0), cin.tie(0), cout.tie(0)
#endif
 
const ll inf = 1ll<<60;
const int iinf=2147483647;
const ll mod = 1e9+7;
const ll maxn=5005;
const double PI=acos(-1);
 
ll pw(ll x, ll p, ll m=mod){
    ll ret=1;
    while (p>0){
        if (p&1){
            ret*=x;
            ret%=m;
        }
        x*=x;
        x%=m;
        p>>=1;
    }
    return ret;
}
 
ll inv(ll a, ll m=mod){
    return pw(a,m-2);
}
 
//=======================================================================================

vector<int> pf[3];
signed main (){
    IOS();
    int n, k; cin>>n>>k;
    REP(i, 3) pf[i].resize(n);
    string str; cin>>str;
    vector<int> pfj(n), pfo(n), pfi(n);
    REP(i,n){
        pf[0][i]=(str[i]=='J');
        pf[1][i]=(str[i]=='O');
        pf[2][i]=(str[i]=='I');
        if (i>0){
            REP(j, 3){
                pf[j][i]+=pf[j][i-1];
            }
        }
    }
    vector<char> mat(3);
    mat[0]='J'; mat[1]='O'; mat[2]='I';
    int ans=inf;
    REP(i,n){
        if (str[i]!='J') continue;
        int a=i;
        bool gg=false;
        REP(j, 3){
            if (a>=n){
                gg=1;
                break;
            }
            //cout<<a<<' '<<str[a]<<endl;
            a=lower_bound(ALL(pf[j]), pf[j][a]+k-(str[a]==mat[j]))-pf[j].begin();
            if (a>=n) {
                gg=1;
                break;
            }
            a++;
        }
        if (!gg) ans=min(ans, a-i-k*3);
    }
    if (ans==inf) ans=-1;
    cout<<ans<<endl;
}

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