Submission #573466

#	Time	Username	Problem	Language	Result	Execution time	Memory
573466		teki	JJOOII 2 (JOI20_ho_t2)	C++11	100 / 100	28 ms	3288 KiB

ho_t2

#include <bits/stdc++.h>

typedef long long ll;

#define pb push_back
#define MS(x,y) memset((x),(y),sizeof((x)))
#define MN 1000000007

using namespace std;

int main()
{
    #if LOCAL_DEBUG
        fstream cin("in.txt");
    #endif

    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);

    int n,k;
    cin>>n>>k;

    int pref[3][n+5];
    MS(pref,0);

    /// J pa O pa I

    string s;
    cin>>s;

    for (int i = 0; i<n; i++) {
        pref[0][i+1] = pref[0][i] + (s[i] == 'J');
        pref[1][i+1] = pref[1][i] + (s[i] == 'O');
        pref[2][i+1] = pref[2][i] + (s[i] == 'I');
    }

    int curr[3];
    int res = INT_MAX/2;

    for (int i = 0; i<=n; i++) {
        for (int j = 0; j<3; j++) curr[j] = pref[j][i];

        int newPos = i;
        int resC = 0;

        for (int j = 0; j<3; j++) {
            auto itJ = lower_bound(pref[j]+newPos,pref[j]+(n+1),curr[j]+k);

            if (itJ == pref[j]+(n+1)) {resC = INT_MAX/2; break; }

            newPos = itJ-pref[j];

            for (int k = 0; k<3; k++) if (k != j) resC += pref[k][newPos]-curr[k];
            for (int k = 0; k<3; k++) curr[k] = pref[k][newPos];
        }

        res = min(res,resC);
    }

    if (res != INT_MAX/2) cout<<res<<endl;
    else cout<<-1<<endl;

    return 0;
}

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