49 lines
872 B
C++
49 lines
872 B
C++
// luogu-judger-enable-o2
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#include<cstdio>
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#include<queue>
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using namespace std;
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const int dr[]={-1,1,0,0};
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const int dc[]={0,0,-1,1};
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struct node { int r,c; };
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const int maxn=1005;
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char mp[maxn][maxn];
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int idx[maxn][maxn],cnt[maxn*maxn];
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int n,m,icnt;
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void bfs(int r,int c,int id)
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{
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idx[r][c]=id;
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queue<node> que;
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que.push((node){r,c});
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while(que.size())
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{
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cnt[id]++;
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node u=que.front(); que.pop();
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for(int i=0;i<4;i++)
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{
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node v=(node){u.r+dr[i],u.c+dc[i]};
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if(v.r>=1&&v.r<=n&&v.c>=1&&v.c<=n&&!idx[v.r][v.c]&&mp[u.r][u.c]!=mp[v.r][v.c])
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{
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idx[v.r][v.c]=id;
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que.push(v);
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}
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}
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}
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}
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int main()
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{
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scanf("%d%d",&n,&m);
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for(int i=1;i<=n;i++) scanf("%s",&mp[i][1]);
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int r,c;
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while(m-->0)
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{
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scanf("%d%d",&r,&c);
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if(idx[r][c]) printf("%d\n",cnt[idx[r][c]]);
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else
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{
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bfs(r,c,++icnt);
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printf("%d\n",cnt[icnt]);
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}
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}
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return 0;
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}
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