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\n", count, max)
}

C++: #include <stdio.h>

int main(void) {

  int nocolor=0,dark=0;

  int map[10][10];

  int x,y,size;
  int nx,ny;
  int dx[12]={1,0,-1,0,1,-1,-1,1,2,0,-2,0};
  int dy[12]={0,1,0,-1,1,1,-1,-1,0,2,0,-2};

  int i;

  for(x=0;x<10;x++) for(y=0;y<10;y++) map[x][y]=0;

  //for(x=0;x<10;x++) for(y=0;y<10;y++) printf("%d ",map[x][y]);
  
  while(scanf("%d,%d,%d",&x,&y,&size)!=EOF) {

    switch(size) {

    case 1:
      
      map[x][y]++;

      for(i=0;i<4;i++) {

	nx=x+dx[i];
	ny=y+dy[i];

	if(nx>=0 && nx<10 && ny>=0 && ny<10) map[nx][ny]++;

      }

      break;

    case 2:

      map[x][y]++;

      for(i=0;i<8;i++) {

	nx=x+dx[i];
	ny=y+dy[i];

	if(nx>=0 && nx<10 && ny>=0 && ny<10) map[nx][ny]++;

      }

      break;

    case 3:

      map[x][y]++;

      for(i=0;i<12;i++) {

	nx=x+dx[i];
	ny=y+dy[i];

	if(nx>=0 && nx<10 && ny>=0 && ny<10) map[nx][ny]++;

      }

      break;

    }

  }

  for(x=0;x<10;x++) {

    for(y=0;y<10;y++) {

      if(map[x][y]==0) nocolor++;

      if(dark<map[x][y]) dark=map[x][y];

    }

  }

  printf("%d\n%d\n",nocolor,dark);

  return 0;

}

C++: //include
//------------------------------------------
#include <bits/stdc++.h> // only for GCC

using namespace std;

//typedef
//------------------------------------------
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<string> vs;
typedef vector<bool> vb;
typedef vector<vb> vvb;
typedef pair<int, int> pii;
typedef long long ll;
typedef unsigned long long ull;

//container util
//------------------------------------------
#define all(a)  (a).begin(),(a).end()
#define rall(a) (a).rbegin(), (a).rend()
#define pb push_back
#define mp make_pair

//repetition
//------------------------------------------
#define loop(i,a,b) for(ull i=(a);i<ull(b);++i)
#define rep(i,n) loop(i,0,n)
#define iter(i,c) for(auto i=(c).begin(); i!=(c).end(); ++i)
#define riter(i,c) for(auto i=(c).rbegin(); i!=(c).rend(); ++i)

//constant
//--------------------------------------------
const double eps = 1e-10;
const double pi  = acos(-1.0);
const double inf = (int)1e8;

// output vector
// ------------------------------------------
namespace std {
    template<typename T>ostream&operator<<(ostream&os, vector<T>const&v){
        iter(it,v) os<<*it<<(it+1==v.end()?"":",");
        return os;
    }
    template<typename T, typename U>ostream&operator<<(ostream&os,const pair<T,U>&p){
        return os << "[" << p.dirst << "," << p.second << "]";
    }
}

//clear memory
// ------------------------------------------
#define clr(a,i) memset((a), (i) ,sizeof(a))

int main(){
    int x,y,s;
    char c;
    int a[14][14]={0};
    while(cin>>x>>c>>y>>c>>s){
      if(s==1){
         a[x+2][y+2]++;
         a[x+1][y+2]++;
         a[x+2][y+1]++;
         a[x+3][y+2]++;
         a[x+2][y+3]++;
      }
      if(s==1){
         a[x+1][y+1]++;
         a[x+1][y+2]++;
         a[x+1][y+3]++;
         a[x+2][y+1]++;
         a[x+2][y+2]++;
         a[x+2][y+3]++;
         a[x+3][y+1]++;
         a[x+3][y+2]++;
         a[x+3][y+3]++;
      }
      if(s==2){
         a[x+1][y+1]++;
         a[x+1][y+2]++;
         a[x+1][y+3]++;
         a[x+2][y+1]++;
         a[x+2][y+2]++;
         a[x+2][y+3]++;
         a[x+3][y+1]++;
         a[x+3][y+2]++;
         a[x+3][y+3]++;
         a[x][y+2]++;
         a[x+2][y]++;
         a[x+2][y+4]++;
         a[x+4][y+2]++;
      }
    }
    int max=0,sum=0;
    loop(i,2,12)loop(j,2,12){
      if(a[i][j]==0) sum++;
      if(a[i][j]>max) max=a[i][j];
    }
    cout << sum << endl;
    cout << max << endl;
}

C++: #include <iostream>
using namespace std;

int main() {
    int x1, y1, size;
    char temp;
    int zeroDensity = 0, maxDensity = 0;
    int paper[10][10];

    for (int i = 0; i != 10; ++i) {
        for (int j = 0; j != 10; ++j) {
            paper[i][j] = 0;
        }
    }

    while (cin >> x1 >> temp >> y1 >> temp >> size) {
        switch (size) {
            case 1:
                paper[x1][y1]++;    // center
                paper[x1][y1-1]++;  // top
                paper[x1+1][y1]++;  // right
                paper[x1][y1+1]++;  // bottom
                paper[x1-1][y1]++;  // left
                break;
            case 2:
                for (int i = -1; i != 2; ++i) { paper[x1 + i][y1-1]++; }
                for (int i = -1; i != 2; ++i) { paper[x1 + i][y1]++; }
                for (int i = -1; i != 2; ++i) { paper[x1 + i][y1+1]++; }
                break;
            case 3:
                for (int i = -1; i != 2; ++i) { paper[x1 + i][y1-1]++; }
                for (int i = -1; i != 2; ++i) { paper[x1 + i][y1]++; }
                for (int i = -1; i != 2; ++i) { paper[x1 + i][y1+1]++; }
                paper[x1][y1-2]++;  // top
                paper[x1+2][y1]++;  // right
                paper[x1][y1+2]++;  // bottom
                paper[x1-2][y1]++;  // left
                break;
        }
    }

    for (int i = 0; i != 10; ++i) {
        for (int j = 0; j != 10; ++j) {
            if (paper[i][j] == 0) {
                ++zeroDensity;
            }
            if (paper[i][j] > maxDensity) {
                maxDensity = paper[i][j];
            }
        }
    }
    cout << zeroDensity << endl;
    cout << maxDensity << endl;
    return 0;
}