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 <bits/stdc++.h>

using namespace std;

typedef long long ll;

const int MAXH = 10;

int h;
vector<vector<int> > st(MAXH, vector<int>(5, 0));

int solve(){
    int ans = 0;

    int mis = 10;

    while(1){
        // DEBUG
        /*
        for(int i=0;i<h;i++){
            for(int j=0;j<5;j++){
                cout << st[i][j] << " ";
            }
            cout << endl;
        }
        */

        // 各行について連鎖するかどうか
        for(int i=0;i<h;i++){
            if(st[i][0] == st[i][1] && st[i][1] == st[i][2] && st[i][2] == st[i][3] && st[i][3] == st[i][4]){
                ans += 5 * st[i][0];
                for(int j=0;j<5;j++) st[i][j] = -1;
            }else if(st[i][0] == st[i][1] && st[i][1] == st[i][2] && st[i][2] == st[i][3]){
                ans += 4 * st[i][0];
                for(int j=0;j<4;j++) st[i][j] = -1;
            }else if(st[i][1] == st[i][2] && st[i][2] == st[i][3] && st[i][3] == st[i][4]){
                ans += 4 * st[i][1];
                for(int j=1;j<5;j++) st[i][j] = -1;
            }else if(st[i][0] == st[i][1] && st[i][1] == st[i][2]){
                ans += 3 * st[i][0];
                for(int j=0;j<3;j++) st[i][j] = -1;
            }else if(st[i][1] == st[i][2] && st[i][2] == st[i][3]){
                ans += 3 * st[i][1];
                for(int j=1;j<4;j++) st[i][j] = -1;
            }else if(st[i][2] == st[i][3] && st[i][3] == st[i][4]){
                ans += 3 * st[i][2];
                for(int j=2;j<5;j++) st[i][j] = -1;
            }
        }

        // cout << ans << endl;

        bool deleted = false;

        for(int i=0;i<h;i++){
            for(int j=0;j<5;j++){
                deleted |= (st[i][j] == -1);
            }
        }

        if(!deleted) return ans;

        vector<vector<int> > prev = st;

        // 次の盤面を生成
        for(int j=0;j<5;j++){
            int nh = h - 1;
            for(int i=h-1;i>=0;i--){
                if(prev[i][j] == -1) continue;
                st[nh][j] = prev[i][j];
                nh--;
            }
            while(nh >= 0){
                st[nh][j] = mis;
                mis++;
                nh--;
            }
            assert(nh < 0);
        }
    }
}

int main(){
    cin.tie(0);
    ios_base::sync_with_stdio(false);
    while(1){
        cin >> h;
        if(h == 0){
            break;
        }
        for(int i=0;i<h;i++){
            for(int j=0;j<5;j++){
                cin >> st[i][j];
            }
        }
        cout << solve() << endl;
    }
}

C++: #include <vector>
#include <queue>
#include <deque>
#include <stack>
#include <algorithm>
#include <functional>
#include <iostream>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <ctime>
#include <cctype>
#include <string>
#include <cstring>

using namespace std;

int main() {
  int n;
  while (cin >> n) {
    if (n == 0) break;

    int field[5][n];
    memset(field, 0, sizeof(field));
    for (int i = 0; i < n; i++) {
      for (int j = 0; j < 5; j++) {
	cin >> field[j][i];
      }
    }

    int ans = 0;
    int memo[5][n];
    while (true) {
      bool change = false;
      for (int y = 0; y < n; y++) {
	int l, r;
	l = r = -1;
	for (int x = 0; x < 5-1; x++) {
	  while (field[x][y] != 0 && field[x][y] == field[x+1][y] && x+1 < 5) {
	    if (l == -1) {
	      l = x;
	      r = x+1;
	    }else {
	      r = x+1;
	    }
	    x++;
	  }
	  // std::cout << "(" << x << "," << y << ") = " << l << " " << r << std::endl;
	  if (r-l+1 >= 3) {
	    for (int i = l; i <= r; i++) {
	      ans += field[i][y];
	      change = true;
	      field[i][y] = 0;
	    }
	  }
	  l = r = -1;
	}
      }
      if (!change) break;

      memset(memo, 0, sizeof(memo));
      for (int x = 0; x < 5; x++) {
	int cnt = 0;
	for (int y = n-1; y >= 0; y--) {
	  cnt += field[x][y] == 0;
	  memo[x][y] = cnt;
	}
      }

      for (int x = 0; x < 5; x++) {
	for (int y = n-1; y >= 0; y--) {
	  if (field[x][y] == 0) continue;
	  if (memo[x][y] == 0) continue;
	  field[x][y+memo[x][y]] = field[x][y];
	  field[x][y] = 0;
	}
      }

    }
    std::cout << ans << std::endl;
  }
}