Submission #896539

#	Time	Username	Problem	Language	Result	Execution time	Memory
896539		Minbaev	Bitaro the Brave (JOI19_ho_t1)	C++17	100 / 100	355 ms	159056 KiB

joi2019_ho_t1

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define pii pair<int,int>
using namespace __gnu_pbds;
using namespace std;
#define pb push_back
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define int long long
#define f first
#define s second
#define pii pair<int,int>
template<class T>bool umax(T &a,T b){if(a<b){a=b;return true;}return false;}
template<class T>bool umin(T &a,T b){if(b<a){a=b;return true;}return false;}
typedef tree<int, null_type, less_equal<int>, rb_tree_tag,
	tree_order_statistics_node_update> ordered_set;
const int mod= 1e9 +7;
const int N=1e5*4;

int binpow (int a, int n) {
	if (n == 0)
		return 1;
	if (n % 2 == 1)
		return binpow (a, n-1) * a;
	else {
		int b = binpow (a, n/2);
		return b * b;
	}
}

void solve(){
	int n,m,k,q;
	
	cin>>n>>m;
	
	char arr[n+1][m+1];
	
	for(int i = 1;i<=n;i++){
		for(int j = 1;j<=m;j++){
			cin>>arr[i][j];
		}
	}
	
	int pref[n+2][m+2];
	int suff[n+2][m+2];
	
	memset(pref,0ll,sizeof(pref));
	memset(suff,0ll,sizeof(suff));
	
	for(int i = 1;i<=n;i++){
		for(int j = m;j>=1;j--){
			pref[i][j] = pref[i][j+1];
			if(arr[i][j]=='O')pref[i][j]++;
		}
	}
	
	for(int j = 1;j<=m;j++){
		for(int i = n;i>=1;i--){
			suff[i][j] = suff[i+1][j];
			if(arr[i][j]=='I')suff[i][j]++;
		}
	}
	
	int ans = 0;
	
	for(int i = 1;i<=n;i++){
		for(int j = 1;j<=m;j++){
			if(arr[i][j]=='J')	
				ans += (pref[i][j]*suff[i][j]);
		}
	}
	
	cout<<ans<<"\n";
		
	
}

 signed main()
{
//	freopen("seq.in", "r", stdin);
//  freopen("seq.out", "w", stdout);
	ios_base::sync_with_stdio(0);cin.tie(NULL);cout.tie(NULL);
	int tt=1;//cin>>tt;
	while(tt--)solve();

}

Compilation message (stderr)

joi2019_ho_t1.cpp: In function 'void solve()':
joi2019_ho_t1.cpp:33:10: warning: unused variable 'k' [-Wunused-variable]
   33 |  int n,m,k,q;
      |          ^
joi2019_ho_t1.cpp:33:12: warning: unused variable 'q' [-Wunused-variable]
   33 |  int n,m,k,q;
      |            ^

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