Go: package main

import (
	"bufio"
	"os"
	"strings"
	"strconv"
	"fmt"
)

func rangeCheck(x, y int) bool {
	if x >= 0 && x <= 9 && y >= 0 && y <= 9 {
		return true
	} else {
		return false
	}
}

func main() {
	scanner := bufio.NewScanner(os.Stdin)
	paper := make([][]int, 10)
	for i := range paper {
		paper[i] = make([]int, 10)
		for j := range paper[i] {
			paper[i][j] = 0
		}
	}
	fmt.Println(paper)
	for scanner.Scan() {
		infos := strings.Split(scanner.Text(), ",")
		x, _ := strconv.Atoi(infos[0])
		y, _ := strconv.Atoi(infos[1])
		s, _ := strconv.Atoi(infos[2])
		// fmt.Println(x, y, s)
		switch s {
		case 1:
			paper[x][y]++
			if rangeCheck(x, y-1) {
				paper[x][y-1]++
			}
			if rangeCheck(x, y+1) {
				paper[x][y+1]++
			}
			if rangeCheck(x-1, y) {
				paper[x-1][y]++
			}
			if rangeCheck(x+1, y) {
				paper[x+1][y]++
			}
			continue
		case 2:
			paper[x][y]++
			if rangeCheck(x-1, y-1) {
				paper[x-1][y-1]++
			}
			if rangeCheck(x, y-1) {
				paper[x][y-1]++
			}
			if rangeCheck(x+1, y-1) {
				paper[x+1][y-1]++
			}
			if rangeCheck(x-1, y) {
				paper[x-1][y]++
			}
			if rangeCheck(x+1, y) {
				paper[x+1][y]++
			}
			if rangeCheck(x-1, y+1) {
				paper[x-1][y+1]++
			}
			if rangeCheck(x, y+1) {
				paper[x][y+1]++
			}
			if rangeCheck(x+1, y+1) {
				paper[x+1][y+1]++
			}
			continue
		case 3:
			paper[x][y]++
			if rangeCheck(x-1,y-1) {
				paper[x-1][y-1]++
			}
			if rangeCheck(x,y-1) {
				paper[x][y-1]++
			}
			if rangeCheck(x+1,y-1) {
				paper[x+1][y-1]++
			}
			if rangeCheck(x-1,y) {
				paper[x-1][y]++
			}
			if rangeCheck(x+1,y) {
				paper[x+1][y]++
			}
			if rangeCheck(x-1,y+1) {
				paper[x-1][y+1]++
			}
			if rangeCheck(x,y+1) {
				paper[x][y+1]++
			}
			if rangeCheck(x+1,y+1) {
				paper[x+1][y+1]++
			}
			if rangeCheck(x,y-2) {
				paper[x][y-2]++
			}
			if rangeCheck(x-2,y) {
				paper[x-2][y]++
			}
			if rangeCheck(x+2,y) {
				paper[x+2][y]++
			}
			if rangeCheck(x,y+2) {
				paper[x][y+2]++
			}
			continue
		}
	}
	count := 0
	max := -1
	for i := range paper {
		for j := range paper[i] {
			if paper[i][j] == 0 {
				count++
			}
			if max >= paper[i][j] {
				max = max
			} else {
				max = paper[i][j]
			}
		}
	}
	fmt.Printf("%d\n%d", count, max)
}

C++: #include <set>
#include <map>
#include <list>
#include <queue>
#include <stack>
#include <cmath>
#include <ctype.h>
#include <ctime>
#include <cstdio>
#include <vector>
#include <string>
#include <bitset>
#include <cctype>
#include <cstdlib>
#include <cstring>
#include <utility>
#include <numeric>
#include <complex>
#include <sstream>
#include <fstream>
#include <iomanip>
#include <cassert>
#include <iostream>
#include <iterator>
#include <algorithm>

using namespace std;

#define REP(i, x, n) for(int i = x; i < n; i++)
#define rep(i, n) REP(i, 0, n)
#define lengthof(x) (sizeof(x) / sizeof(*(x)))
#define FILL(ptr, value) FILL_((ptr), sizeof(ptr)/sizeof(value), (value))
template <typename T>
void FILL_(void * ptr, size_t size, T value){
  std::fill((T*)ptr, (T*)ptr+size, value);
}
//4方向ベクトル→↑←↓
int dx[] ={1,0,-1,0};
int dy[] ={0,-1,0,1};
int board[15][15];
int x,y,size;
int nx,ny;
int ans1,ans2;
int main()
{
  ans1 = 0;
  for(int i = 0;i <10;i++){
    for(int j = 0;j < 10;j++){
      board[j][i] = 0;
    }
  }
  while(scanf("%d,%d,%d",&x,&y,&size) !=EOF){
    if(size ==1){
      board[y][x] +=1;
      for(int i = 0;i < 4;i++){
	nx = x +dx[i];
	ny = y +dy[i];
	if(nx <0 ||nx >10||ny <0||ny >10)
	  continue;
	board[ny][nx] +=1;
      }
    }else if(size ==2){
      for(int i = -1;i <=1;i++){
	for(int j = -1;j <=1;j++){
	  nx = x +j;
	  ny = y +i;
	  if(nx <0 ||nx >=10||ny <0||ny >=10)
	    continue;
	  board[ny][nx] +=1;
	}
      }
    }else if(size ==3){
      for(int i = -2;i <=2;i++){
	for(int j = -2;j <=2;j++){
	  if(i == -2&&j ==0){
	    board[y+i][x] +=1;
	  }else if(i == -1&&(j !=-2&&j !=2)){
	    board[y+i][x+j] +=1;
	  }else if(i == 0){
	    board[y+i][x+j] +=1;
	  }else if(i == 1&&(j !=-2&&j !=2)){
	    board[y+i][x+j] +=1;
	  }else if(i ==2&&j ==0){
	    board[y+i][x] +=1;
	  }
	}
      }
    }
  }
  ans2 = 0; 
    for(int i = 0;i <10;i++){
      for(int j = 0;j < 10;j++){
	if(board[i][j] == 0){
	  ans1++;
	}
	if(board[i][j] > ans2){
	  ans2 = board[i][j];
	}
      }
    }
  cout <<ans1<<endl;
  cout <<ans2<<endl;
  return 0;
}

C++: #include <iostream>
#include <cstdio>
#include <cmath>
#include <vector>
#include <string>
#include <queue>
#include <set>
#include <algorithm>

using namespace std;

int paper[10][10];

bool inField(int argX, int argY) {
	if (argX < 0 || argX > 9 || argY < 0 || argY > 9) return false;
	return true;
}

int main() {
	string input = "";
	cin >> input;
	
	int dx[13] = { 0, 0, 1, 0, -1, 1, 1, -1, -1, 0, 2, 0, -2 };
	int dy[13] = { 0, -1, 0, 1, 0, -1, 1, 1, -1, -2, 0, 2, 0 };
	
	for (int x = 0; x < 10; x++) {
		for (int y = 0; y < 10; y++) {
			paper[x][y] = 0;
		}
	}
	
	while (input.size() > 0) {
		
		int dropX = input[0] - '0';
		int dropY = input[2] - '0';
		int dropSize = input[4] - '0';
		int dropNum;
		
		if (dropSize == 1) dropNum = 5;
		else if (dropSize == 2) dropNum = 9;
		else dropNum = 13;
		
		for (int i = 0; i < dropNum; i++) {
			if (!inField(dropX + dx[i], dropY + dy[i])) continue;
			
			paper[dropX + dx[i]][dropY + dy[i]]++;
		}
		
		input = "";
		cin >> input;
	}
	
	int blankNum = 0;
	int maxDensity = 0;
	for (int x = 0; x < 10; x++) {
		for (int y = 0; y < 10; y++) {
			if (paper[x][y] == 0) {
				blankNum++;
			} else if (paper[x][y] > maxDensity) {
				maxDensity = paper[x][y];
			}
		}
	}
	
	cout << blankNum << endl;
	cout << maxDensity << endl;
	
	return 0;
}

C++: #include <iostream>
#include <algorithm>
#include <cstdio>
#define rep(i,n) for(int i=0;i < n;i++)

using namespace std;

int p[10][10];
int cnt = 0,Max = 0;
void ink(int x,int y){
  if(0<=x && x < 10|| 0<=y && y<10)p[x][y]++;
}

int main(){

    rep(i,10)rep(j,10){
      p[i][j] = 0;
    }

  while(1){

    int x,y,size;

    scanf("%d,%d,%d",&x,&y,&size);
    if(cin.eof())break;
    if(size == 1){
      ink(x,y);
      ink(x+1,y);
      ink(x-1,y);
      ink(x,y+1);
      ink(x,y-1);
    }else  if(size == 2){
      ink(x,y);
      ink(x+1,y);
      ink(x-1,y);
      ink(x,y+1);
      ink(x,y-1);
      ink(x+1,y+1);
      ink(x-1,y+1);
      ink(x-1,y-1);
      ink(x+1,y-1);
    }else  if(size == 3){
      ink(x,y);
      ink(x+1,y);
      ink(x-1,y);
      ink(x,y+1);
      ink(x,y-1);
      ink(x+1,y+1);
      ink(x-1,y+1);
      ink(x-1,y-1);
      ink(x+1,y-1);
      ink(x+2,y);
      ink(x-2,y);
      ink(x,y+2);
      ink(x,y-2);
    }
     cnt =Max = 0;
    rep(i,10)rep(j,10){
      if(p[i][j]==0)cnt++;
      Max = max(Max,p[i][j]);
    }
}
    cout << cnt <<"\n" << Max << endl;


  return 0;
}