Submission #183860

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Source Code Expand

#include <vector>
#include <list>
#include <map>
#include <set>
#include <stack>
#include <queue>
#include <deque>
#include <algorithm>
#include <utility>
#include <functional>
#include <sstream>
#include <iostream>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
#include <ctime>
#include <climits>
#include <cassert>
#include <memory>
#include <time.h>
using namespace std;
inline int toInt(string s) {int v; istringstream sin(s);sin>>v;return v;}
template<class T> inline string toString(T x) {ostringstream sout;sout<<x;return sout.str();}
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<string> vs;
typedef pair<int, int> pii;
typedef long long ll;
#define ALL(a) (a).begin(),(a).end()
#define RALL(a) (a).rbegin(),(a).rend()
#define EXIST(s,e) ((s).find(e)!=(s).end())
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n) FOR(i,0,n)
const double EPS = 1e-9;
const double PI  = acos(-1.0);

typedef vector<vvi> vvvi;

int main(){
	int n,m;
	cin>>n>>m;
	vvi c(n,vi(m));
	REP(i,n){
		REP(j,m){
			cin>>c[i][j];
		}
	}

	vvvi sum(2,vvi(n+1,vi(m+1)));
	REP(col,2){
		sum[col][1][1]=((1+1)%2==col)*c[0][0];
		REP(i,n){
			REP(j,m){
				if(j==0){
					sum[col][i+1][j+1]=((i+j)%2==col)*c[i][j];
				}else{
					sum[col][i+1][j+1]=sum[col][i+1][j]+((i+j)%2==col)*c[i][j];
				}
			}
		}
		REP(j,m){
			FOR(i,1,n){
				sum[col][i+1][j+1]+=sum[col][i][j+1];
			}
		}
	}

	int ans=0;
	REP(fy,n){
		REP(fx,m){
			FOR(ty,fy,n){
				vi num(2);
				FOR(tx,fx,m){
					REP(i,2){
						num[i]=sum[i][ty+1][tx+1]-sum[i][ty+1][fx]-sum[i][fy][tx+1]+sum[i][fy][fx];
					}
					if(num[0]==num[1]){
						ans=max(ans,(ty-fy+1)*(tx-fx+1));
						//cerr<<ans<<endl;
					}
				}
			}
		}
	}
	cout<<ans<<endl;
}

Submission Info

Judge Result