Submission #70466

#	Time	Username	Problem	Language	Result	Execution time	Memory
70466		Diuven	스탬프 수집 (JOI16_ho_t2)	C++14	100 / 100	6 ms	3244 KiB

2016_ho_t2

#include <bits/stdc++.h>
using namespace std;
typedef pair<int, int> pii;
typedef long long ll;
const int MX=100010, inf=2e9;

int n;
char S[MX];

int Jcnt[MX], Icnt[MX];
ll base;

ll J(){
  ll res=base;
  for(int i=1; i<=n; i++)
    if(S[i]=='O') res+=Icnt[i];
  return res;
}

ll I(){
  ll res=base;
  for(int i=n; i>=1; i--)
    if(S[i]=='O') res+=Jcnt[i];
  return res;
}

ll O(){
  ll mx=0;
  for(int i=1; i<=n; i++){
    mx=max(mx, 1LL*Jcnt[i-1]*Icnt[i]);
  }
  return base+mx;
}

int main(){
  ios::sync_with_stdio(0); cin.tie(0);
  cin>>n>>(S+1);
  for(int i=1; i<=n; i++)
    Jcnt[i]=Jcnt[i-1]+(S[i]=='J');
  for(int i=n; i>=1; i--)
    Icnt[i]=Icnt[i+1]+(S[i]=='I');
  for(int i=1; i<=n; i++)
    if(S[i]=='O') base+=1LL*Jcnt[i]*Icnt[i];
  ll ans=max({J(), I(), O()});
  cout<<ans;
  return 0;
}

• Subtask 1: 30 / 30
• Subtask 2: 20 / 20
• Subtask 3: 50 / 50