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 <bitset>
#include <complex>
#include <deque>
#include <exception>
#include <fstream>
#include <functional>
#include <iomanip>
#include <ios>
#include <iosfwd>
#include <iostream>
#include <istream>
#include <iterator>
#include <limits>
#include <list>
#include <locale>
#include <map>
#include <memory>
#include <new>
#include <numeric>
#include <ostream>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <stdexcept>
#include <streambuf>
#include <string>
#include <typeinfo>
#include <utility>
#include <valarray>
#include <vector>
#include <climits>

#define rep(i, a, n) for(int i=a;i < n;i++)
#define all(e) e.begin(), e.end()
#define INF (1 << 30)
#define INFL (1LL << 55)

using namespace std;

class Solver {
public:
    Solver(int size) {
        this->H = size;
    }

    void solve() {
        input();
        rep(z, 0, 20) {
            //加点・消去パート
            rep(h, 0, H) {
                int prev = V[0][h];
                int cont = 1;
                rep(w, 1, 5) {
                    if (V[w][h] == prev) {
                        cont++;
                    } else {
                        if (cont >= 3) {
                            ans += cont * prev;
                            rep(i, w - cont, w) {
                                V[i][h] = 0;
                            }
                        }
                        prev = V[w][h];
                        cont = 1;
                    }

                }
                if (cont >= 3) {
                    ans += cont * prev;
                    rep(i, 5 - cont, 5) {
                        V[i][h] = 0;
                    }
                }
            }

            //再配置パート
            rep(w, 0, 5) {
                rep(h, 0, H) {
                    if (V[w][h] != 0) {
                        int tmp = h - 1;
                        while (tmp >= 0) {
                            if (V[w][tmp] != 0) break;
                            tmp--;
                        }
                        swap(V[w][h], V[w][tmp + 1]);
                    }
                }
            }
            /*
            cerr<<"turn"<<z<<", "<<ans<<endl;
            for (int h = H - 1; h >= 0; h--) {
                rep(w, 0, 5) {
                    cerr << V[w][h] << " ";
                }
                cerr << endl;
            }*/
        }


        cout << ans << endl;
    }

private:
    int H;
    vector<vector<int>> V; // フィールド
    long long ans = 0;

    void input() {
        V.resize(5, vector<int>(H));
        for(int h=H-1;h>=0;h--) {
            rep(w, 0, 5) {
                cin >> V[w][h];
            }
        }
    }
};

int main() {

    int N;
    while (cin >> N, N) {
        Solver(N).solve();
    }


    return 0;
}