> #include<iostream>
> #include<queue>
> using namespace std;
> #define MAX 101
> int set[MAX][MAX];
> int visited[MAX][MAX];
> int step[MAX][MAX];
> int move[4][2]={{0,1},{0,-1},{1,0},{-1,0}};
> int r,c,k;
> int result;
> struct farm
> {
> 	int r,c;
> };
> queue<farm> q;
> void BFS(int x,int y)
> {	
> 
> 	visited[x][y]=1;
> 	farm m;
> 	m.r =x;
> 	m.c =y;
> 	q.push(m);
> 	step[x][y] = 1;
> 	result = 1 ;
> 	while(!q.empty()){
> 		farm temp = q.front();
> 		q.pop();
> 		for(int i=0;i<4;i++)
> 		{
> 			x = temp.r;
> 			y = temp.c;
> 			x+=move[i][0];
> 			y+=move[i][1];
> 			if(x>=1&&x<=r&&y>=1&&y<=c)
> 			{
> 				if(set[x][y]&&!visited[x][y]){
> 					visited[x][y]=1;
> 					result++;
> 					m.r = x;
> 					m.c = y;
> 					q.push(m);
> 					
> 				}
> 			}
> 
> 		}
> 	}
> 
> }
> int main()
> {
> 	
> 	cin>>r>>c>>k;
> 	int a,b;
> 	int final = 0;
> 	for(int i=0;i<k;i++){
> 		cin>>a>>b;
> 		set[a][b] = 1;
> 	}
> 	for(int i=1;i<=r;i++){
> 		for(int j=1;j<=c;j++){
> 			if(set[i][j]==0||visited[i][j]==1)	
> 				continue;
> 			
> 			BFS(i,j);
> 			if(result > final)
> 				final = result;
> 
> 		}
> 	}
> 	cout<<final<<endl;
> 	return 0;
> }

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