Submission #155642

#	Time	Username	Problem	Language	Result	Execution time	Memory
155642		popovicirobert	Bitaro the Brave (JOI19_ho_t1)	C++14	100 / 100	118 ms	53384 KiB

joi2019_ho_t1

#include <bits/stdc++.h>
#define lsb(x) (x & (-x))
#define ll long long
#define ull unsigned long long



#if 0
const int MOD = ;

inline int lgput(int a, int b) {
    int ans = 1;
    while(b > 0) {
        if(b & 1) ans = (1LL * ans * a) % MOD;
        b >>= 1;
        a = (1LL * a * a) % MOD;
    }
    return ans;
}

inline void mod(int &x) {
    if(x >= MOD)
        x -= MOD;
}

inline void add(int &x, int y) {
    x += y;
    mod(x);
}

inline void sub(int &x, int y) {
    x += MOD - y;
    mod(x);
}

inline void mul(int &x, int y) {
    x = (1LL * x * y) % MOD;
}

inline int inv(int x) {
    return lgput(x, MOD - 2);
}
#endif

#if 0
int fact[], invfact[];

inline void prec(int n) {
    fact[0] = 1;
    for(int i = 1; i <= n; i++) {
        fact[i] = (1LL * fact[i - 1] * i) % MOD;
    }
    invfact[n] = lgput(fact[n], MOD - 2);
    for(int i = n - 1; i >= 0; i--) {
        invfact[i] = (1LL * invfact[i + 1] * (i + 1)) % MOD;
    }
}

inline int comb(int n, int k) {
    if(n < k) return 0;
    return (1LL * fact[n] * (1LL * invfact[k] * invfact[n - k] % MOD)) % MOD;
}
#endif

using namespace std;

const int MAXN = 3005;

char mat[MAXN + 1][MAXN + 1];
int down[MAXN + 1][MAXN + 1];

int main() {
#if 0
    ifstream cin("A.in");
    ofstream cout("A.out");
#endif
    int i, j, n, m;
    ios::sync_with_stdio(false);
    cin.tie(0), cout.tie(0);

    cin >> n >> m;
    for(i = 1; i <= n; i++) {
        cin >> mat[i] + 1;
    }

    for(i = n; i >= 1; i--) {
        for(j = 1; j <= m; j++) {
            down[i][j] = down[i + 1][j] + (mat[i][j] == 'I');
        }
    }

    ll ans = 0;
    for(i = 1; i <= n; i++) {
        int cnt = 0;
        for(j = m; j >= 1; j--) {
            if(mat[i][j] == 'J') {
                ans += 1LL * cnt * down[i][j];
            }
            cnt += (mat[i][j] == 'O');
        }
    }
    cout << ans;

    return 0;
}

Compilation message (stderr)

joi2019_ho_t1.cpp: In function 'int main()':
joi2019_ho_t1.cpp:83:23: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
         cin >> mat[i] + 1;
                ~~~~~~~^~~

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