Submission #1095490

#	Time	Username	Problem	Language	Result	Execution time	Memory
1095490		TrinhKhanhDung	Bitaro the Brave (JOI19_ho_t1)	C++14	100 / 100	103 ms	88656 KiB

joi2019_ho_t1

#include <bits/stdc++.h>
#define ll long long
#define fi first
#define se second
#define sz(x) (int)x.size()
#define ALL(v) v.begin(),v.end()
#define MASK(k) (1LL << (k))
#define BIT(x, i) (((x) >> (i)) & 1)
#define oo (ll)1e18 + 10
#define INF (ll)1e9
#define MOD (ll)(1e9 + 7)

using namespace std;

template<class T1, class T2>
    bool maximize(T1 &a, T2 b){if(a < b){a = b; return true;} return false;}

template<class T1, class T2>
    bool minimize(T1 &a, T2 b){if(a > b){a = b; return true;} return false;}

template<class T1, class T2>
    void add(T1 &a, T2 b){a += b; if(a >= MOD) a -= MOD;}

template<class T1, class T2>
    void sub(T1 &a, T2 b){a -= b; if(a < 0) a += MOD;}

template<class T>
    void cps(T &v){sort(ALL(v)); v.resize(unique(ALL(v)) - v.begin());}

const int MAX = 3003;

int N, M;
int preO[MAX][MAX], preI[MAX][MAX];
string mat[MAX];

void solve(){
    cin >> N >> M;
    for(int i = 1; i <= N; i++){
        cin >> mat[i];
        mat[i] = " " + mat[i];
    }

    clock_t start = clock();

    for(int i = N; i >= 1; i--){
        for(int j = M; j >= 1; j--){
            preO[i][j] = preO[i][j + 1] + (mat[i][j] == 'O');
            preI[i][j] = preI[i + 1][j] + (mat[i][j] == 'I');
        }
    }

    ll ans = 0;
    for(int i = 1; i <= N; i++) for(int j = 1; j <= M; j++) if(mat[i][j] == 'J'){
        ans += 1LL * preO[i][j + 1] * preI[i + 1][j];
    }

    cout << ans << '\n';


    cerr << "Time elapsed: " << clock() - start << " ms\n";
}

int main(){
    ios_base::sync_with_stdio(0); cin.tie(0);
//     freopen("bdbang.inp","r",stdin);
//     freopen("bdbang.out","w",stdout);

    int t = 1;
//    cin >> t;
    while(t--)
        solve();

    return 0;
}

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