Go: package main

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

func main() {
	io := NewIo()
	defer io.Flush()
	for {
		h := io.NextInt()
		if h == 0 {
			break
		}
		p := make([][]int, h)
		for i := 0; i < h; i++ {
			p[i] = make([]int, 5)
			for j := 0; j < 5; j++ {
				p[i][j] = io.NextInt()
			}
		}
		ans := 0
		for {
			sc := puyo(p, h)
			if sc == 0 {
				break
			}
			fall(p, h)
			ans += sc
		}
		io.Println(ans)
	}
}

func puyo(p [][]int, h int) int {
	sc := 0
	for i := 0; i < h; i++ {
		for j := 0; j < 3; j++ {
			var cnt int
			for cnt = 1; j+cnt < 5; cnt++ {
				if p[i][j] != p[i][j+cnt] {
					break
				}
			}
			if cnt > 2 {
				sc += p[i][j]*cnt
				for k := 0; k < cnt; k++ {
					p[i][j+k] = 0
				}
			}
		}
	}
	return sc
}

func fall(p [][]int, h int) {
	for j := 0; j < 5; j++ {
		for k := 1; k < h; k++ {
			for i := h - 1; i >= k; i-- {
				if p[i][j] == 0 {
					p[i][j] = p[i-1][j]
					p[i-1][j] = 0
				}
			}
		}
	}
}

// I/O template
type Io struct {
	reader    *bufio.Reader
	writer    *bufio.Writer
	tokens    []string
	nextToken int
}

func NewIo() *Io {
	return &Io{
		reader: bufio.NewReader(os.Stdin),
		writer: bufio.NewWriter(os.Stdout),
	}
}

func (io *Io) Flush() {
	err := io.writer.Flush()
	if err != nil {
		panic(err)
	}
}

func (io *Io) NextLine() string {
	var buff []byte
	for {
		line, isPrefix, err := io.reader.ReadLine()
		if err != nil {
			panic(err)
		}
		buff = append(buff, line...)
		if !isPrefix {
			break
		}
	}
	return string(buff)
}

func (io *Io) Next() string {
	for io.nextToken >= len(io.tokens) {
		line := io.NextLine()
		io.tokens = strings.Fields(line)
		io.nextToken = 0
	}
	s := io.tokens[io.nextToken]
	io.nextToken++
	return s
}

func (io *Io) NextInt() int {
	i, err := strconv.Atoi(io.Next())
	if err != nil {
		panic(err)
	}
	return i
}

func (io *Io) NextFloat() float64 {
	i, err := strconv.ParseFloat(io.Next(), 64)
	if err != nil {
		panic(err)
	}
	return i
}

func (io *Io) Println(a ...interface{}) {
	fmt.Fprintln(io.writer, a...)
}

func (io *Io) Printf(format string, a ...interface{}) {
	fmt.Fprintf(io.writer, format, a...)
}

func (io *Io) PrintIntSlice(a []int) {
	b := []interface{}{}
	for _, x := range a {
		b = append(b, x)
	}
	io.Println(b...)
}

func (io *Io) PrintStringSlice(a []string) {
	b := []interface{}{}
	for _, x := range a {
		b = append(b, x)
	}
	io.Println(b...)
}

func Log(name string, value interface{}) {
	fmt.Fprintf(os.Stderr, "%s=%+v\n", name, value)
}

func ExampleIo() {
	io := NewIo()
	defer io.Flush()
	a := make([]int, 0, 3)
	a[0], a[1], a[2] = io.NextInt(), io.NextInt(), io.NextInt()
	io.Println(a)
	io.PrintIntSlice(a)
	Log("io", a)
}

C++: #include <algorithm>
#include <iostream>
#include <limits.h>
#include <math.h>
#include <set>
#include <stack>
#include <stdlib.h>
#include <string>
#include <vector>

#define el endl
#define fd fixed
#define INF INT_MAX/2-1
#define pb push_back

using namespace std;

int calcmin(vector<int> v[5])  {
  int min = v[0].size();
  for (int i = 1; i < 5; i++) {
    if (min > v[i].size()) min = v[i].size();
  }
  return min;
}

int main() {
  int h, tmp, score;
  bool flag;
  while (cin >> h, h) {
    vector<int> column[5];
    int memo[h][5];
    flag = true;
    score = 0;
    for (int i = 0; i < h; i++) {
      for (int j = 0; j < 5; j++) {
        cin >> tmp;
        memo[i][j] = tmp;
      }
    }
    for (int i = 0; i < h; i++) {
      for (int j = 0; j < 5; j++) {
        column[j].pb(memo[h-i-1][j]);
      }
    }
    while (flag) {
      flag = false;
      vector<int> del_col, del_row;
      for (int i = 0; i < calcmin(column); i++) {
        if (column[0][i] == column[1][i] && column[1][i] == column[2][i] && column[2][i] == column[3][i] && column[3][i] == column[4][i]) {
          score += 5*column[2][i], flag = true;
          del_row.pb(i), del_row.pb(i), del_row.pb(i), del_row.pb(i), del_row.pb(i);
          del_col.pb(0), del_col.pb(1), del_col.pb(2), del_col.pb(3), del_col.pb(4);
        } else if (column[0][i] == column[1][i] && column[1][i] == column[2][i] && column[2][i] == column[3][i]) {
          score += 4*column[2][i], flag = true;
          del_row.pb(i), del_row.pb(i), del_row.pb(i), del_row.pb(i);
          del_col.pb(0), del_col.pb(1), del_col.pb(2), del_col.pb(3);
        } else if (column[1][i] == column[2][i] && column[2][i] == column[3][i] && column[3][i] == column[4][i]) {
          score += 4*column[2][i], flag = true;
          del_row.pb(i), del_row.pb(i), del_row.pb(i), del_row.pb(i);
          del_col.pb(1), del_col.pb(2), del_col.pb(3), del_col.pb(4);
        } else if (column[0][i] == column[1][i] && column[1][i] == column[2][i]) {
          score += 3*column[2][i], flag = true;
          del_row.pb(i), del_row.pb(i), del_row.pb(i);
          del_col.pb(0), del_col.pb(1), del_col.pb(2);
        } else if (column[1][i] == column[2][i] && column[2][i] == column[3][i]) {
          score += 3*column[2][i], flag = true;
          del_row.pb(i), del_row.pb(i), del_row.pb(i);
          del_col.pb(1), del_col.pb(2), del_col.pb(3);
        } else if (column[2][i] == column[3][i] && column[3][i] == column[4][i]) {
          score += 3*column[2][i], flag = true;
          del_row.pb(i), del_row.pb(i), del_row.pb(i);
          del_col.pb(2), del_col.pb(3), del_col.pb(4);
        }
      }
      for (int i = del_col.size()-1; i >= 0; i--) {
        column[del_col[i]].erase(column[del_col[i]].begin()+del_row[i]);
      }
    }
    cout << score << el;
  }
}

C++: #include <bits/stdc++.h>
#define INF 1e18
#define int long long
#define Rep(i, a, n) for (int i = (a); i < (n); i++)
#define Repr(i, n, a) for (int i = (n); i >= (a); i--)
#define rep(i, n) Rep(i, 0, n)
#define repr(i, n) Repr(i, n, 0)
#define all(a) (a).begin(), (a).end()
using namespace std;
typedef pair<int, int> P;
typedef pair<int, P> PP;
const int mod = 1000000007;

signed main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);

    int H;
    while (1)
    {
        cin >> H;
        if (H == 0)
            break;
        int field[10][6] = {};
        for (int i = 0; i < H; i++)
            for (int j = 0; j < 5; j++)
                cin >> field[i][j];
        int ans = 0;
        while (1)
        {
            int score = 0;
            for (int i = 0; i < H; i++)
            {
                int cnt = 1;
                for (int j = 0; j < 4; j++)
                {
                    if (field[i][j] == field[i][j + 1] && field[i][j] != -1)
                        cnt++;
                    else
                    {
                        if (cnt >= 3)
                        {
                            score += cnt * field[i][j];
                            for (int k = j; k > j - cnt; k--)
                                field[i][k] = -1;
                        }
                        cnt = 1;
                    }
                }
                if (cnt >= 3)
                {
                    score += cnt * field[i][4];
                    for (int j = 4; j > 4 - cnt; j--)
                        field[i][j] = -1;
                }
            }
            if (score == 0)
                break;
            ans += score;
            for (int i = 0; i < 5; i++)
            {
                vector<int> v;
                for (int j = 0; j < H; j++)
                    if (field[j][i] != -1)
                        v.push_back(field[j][i]);
                reverse(all(v));
                for (int j = 0; j < v.size(); j++)
                    field[H - j - 1][i] = v[j];
                for (int j = v.size(); j < H; j++)
                    field[H - j - 1][i] = -1;
            }
            // for (int i = 0; i < H; i++)
            // {
            //     for (int j = 0; j < 5; j++)
            //         cout << field[i][j] << " ";
            //     cout << endl;
            // }
            // cout << endl;
        }
        cout << ans << endl;
    }
}