1 #include<cstdio> 2 #include<queue> 3 #include<cstring> 4 using namespace std; 5 const int dx[]={0,0,-1,1},dy[]={1,-1,0,0}; 6 struct Point{int x,y;Point(const int &a,const int &b){x=a;y=b;}Point(){}}; 7 queue<Point>q; 8 int n,m,d[1000][1000],num; 9 char s[1000][1000],CH[20];10 inline void putint(int x)11 {12     num=0;  13     while(x>0){CH[++num]=x%10;x/=10;}14     while(num)putchar(CH[num--]+48);15     putchar(‘ ‘);16 }17 int main()18 {19     scanf("%d%d",&n,&m);20     memset(d,0x7f,sizeof(d));21     for(int i=0;i<n;i++)22       {23           scanf("%s",s[i]);24           for(int j=0;j<m;j++)25             if(s[i][j]==‘1‘)26               {27                 d[i][j]=0;28                 q.push(Point(i,j));29               }30       }31     while(!q.empty())32       {33           for(int i=0;i<4;i++)34             {35                 int tx=dx[i]+q.front().x,ty=dy[i]+q.front().y;36                 if(tx>=0&&tx<n&&ty>=0&&ty<m&&d[q.front().x][q.front().y]+1<d[tx][ty])37                   {38                       q.push(Point(tx,ty));39                       d[tx][ty]=d[q.front().x][q.front().y]+1;40                   }41             }42           q.pop();43       }44     for(int i=0;i<n;i++)45       {46           for(int j=0;j<m;j++)47             if(d[i][j])putint(d[i][j]);48             else {putchar(‘0‘);putchar(‘ ‘);}49           putchar(‘\n‘);50       }51     return 0;52 }