Submission #1986890

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Source Code Expand

#include <bits/stdc++.h>

using std::max;

const int N=2010;

int n,m,up[N][N];
bool map[N][N],mp[N][N];

void Init() {
	scanf("%d%d",&n,&m);
	for (int i=0;i<n;++i)
		for (int j=0;j<m;++j) {
			char ch=getchar();
			while (ch!='#' && ch!='.') ch=getchar();
			if (ch=='#') map[i][j]=0;
			else map[i][j]=1;
		}
}

int que[N],ans;
void Work(int *up) {
	int top=0; up[m]=-1;
	for (int i=1;i<=m;++i) {
		while (top && up[que[top]]>up[i]) {
			ans=max(ans,(up[que[top]]+1)*(i-que[top-1]));
			top--;
		}
		que[++top]=i;
	}
}

void Solve() {
	for (int i=1;i<n;++i) 
		for (int j=1;j<m;++j) 
			mp[i][j]=map[i][j]^map[i-1][j]^map[i][j-1]^map[i-1][j-1]^1;
	for (int i=1;i<n;++i)
		for (int j=1;j<m;++j) {
			if (mp[i][j]) up[i][j]=up[i-1][j]+1;
			else up[i][j]=0;
		}
	ans=max(n,m);
	for (int i=1;i<n;++i) Work(up[i]);
	printf("%d\n",ans);
}

int main() {
	Init();
	Solve();
	return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘void Init()’:
./Main.cpp:11:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&n,&m);
                     ^

Judge Result