Go: package main

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

func main() {
	io := NewIo()
	defer io.Flush()
	for {
		_, M := io.NextInt(), io.NextInt()
		if M == 0 {
			break
		}
		r := io.NextInt()
		t, m, s := make([]int, r), make([]int, r), make([]int, r)
		for i := 0; i < r; i++ {
			t[i], _, m[i], s[i] = io.NextInt(), io.NextInt(), io.NextInt()-1, io.NextInt()
		}
		q := io.NextInt()
		for i := 0; i < q; i++ {
			ss, ee, mm := io.NextInt(), io.NextInt(), io.NextInt()-1
			x := make([]int, 1300)
			for j := 0; j < r; j++ {
				if m[j] == mm {
					if s[j] == 1 {
						x[t[j]]++
					} else {
						x[t[j]]--
					}
				}
			}
			for j := 1; j < 1300; j++ {
				x[j] = x[j] + x[j-1]
			}
			ans := 0
			for j := ss; j < ee; j++ {
				if x[j] > 0 {
					ans++
				}
			}
			io.Println(ans)
		}
	}
}

// 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<iostream>
using namespace std;

int main()
{
loop:
  int min = 1 << 30, max = 0, sum = 0, n;
  cin >> n;
  if(!n)
    return 0;
  for(int i = 0; i < n; i++)
  {
    int tmp;
    cin >> tmp;
    max = max < tmp ? tmp : max;
    min = min > tmp ? tmp : min;
    sum += tmp;
  }
  cout << (sum - max - min) / (n - 2) << endl;
  goto loop;
}

C++: #include <iostream>
#include <vector>

using namespace std;

class student {
public:
    vector<int> st, ed;
    int cnt;
    student() { cnt = 0; }
};

int main()
{
    int N; // PC数
    int M; // 学生数

    while (cin >> N >> M, N || M) {
        int r;  // 利用記録数
        int q;  // 質問数
        vector<student> std(M + 1);

        // 登録
        cin >> r;
        for (int i = 0; i < r; i++) {
            int t, n, m, s;  // s(1: ログイン, 0: ログアウト), 時刻tにPCnで学生mが
            cin >> t >> n >> m >> s;

            if (s == 1) { // ログイン
                if (std[m].cnt == 0) {  // まだログインしていない
                    std[m].st.push_back(t);
                }
                std[m].cnt++;
            }
            else { // ログアウト
                if (std[m].cnt == 1) 
                    std[m].ed.push_back(t);
                std[m].cnt--;
            }
        }

        // 質問
        cin >> q;
        for (int i = 0; i < q; i++) {
            int ts, te, m;
            int ans = 0;

            cin >> ts >> te >> m;

            for (int j = 0; j < std[m].st.size(); j++) {
                if (std[m].ed[j] <= ts)
                    continue;
                if (std[m].st[j] >= te)
                    break;
                
                if (std[m].st[j] <= ts && std[m].ed[j] >= te) {
                    ans += te - ts;
                    break;
                }
                if (std[m].st[j] <= ts && std[m].ed[j] < te)
                    ans += std[m].ed[j] - ts;
                else if (std[m].st[j] >= ts && std[m].ed[j] >= te) {
                    ans += te - std[m].st[j];
                    break;
                }
                else if (std[m].st[j] >= ts && std[m].ed[j] < te) 
                    ans += std[m].ed[j] - std[m].st[j];
            }
            cout << ans << endl;
        }
    }

    return 0;
}

C++: #include <bits/stdc++.h> 
#define REP(i,n) for(int i=0; i< (n); ++i)
#define FOR(i,s,n) for(int i=s; i< (n); ++i)
using namespace std;
using vi = vector<int>;
using vvi = vector<vi>;

int main() {
    cin.tie(0);
    ios_base::sync_with_stdio(false);
 
    cout << fixed << setprecision(30);
 
    while (true){
        int N, M; cin >> N >> M;
        if (N == 0) break;
        int r; cin >> r;
 
        vvi students(M, vi(1262, 0));
 
        REP(i, r){
            int t, n, m, s;
            cin >> t >> n >> m >> s; m--;
            if (s == 1){
                students[m][t]++;
            } else {
                students[m][t]--;
            }
        }
 
        REP(i, M) FOR(j, 1, 1262) students[i][j] += students[i][j - 1];
 
        int q; cin >> q;
        REP(i, q){
            int ts, te, m;
            cin >> ts >> te >> m; m--;
            int cnt = 0;
            FOR(j, ts, te) if (students[m][j] >= 1) cnt++;
            cout << cnt << endl;
        }
    }
    return 0;
}

C++: #include<cstdio>
#include<iostream>
#include<algorithm>
#include<vector>
 
using namespace std;
 
int main(){
  int t[1123],n[1123],m[1123],s[1123],N,M,r,i,j,k;
  int stud[1269];
  while(1){
    cin>>N>>M;
    // cout<<N<<","<<M<<endl;
    if(N==0 && M==0)
      break;
    cin>>r;
    for(i=0;i<r;i++){
      cin>>t[i]>>n[i]>>m[i]>>s[i];
    }
    int q,ts,te,mm,re=0;
    cin>>q;
    for(i=0;i<q;i++){
      re=0;
      cin>>ts>>te>>mm;
      fill(stud,(stud+1269),0);
      for(j=0;j<r;j++)
    if(m[j]==mm)stud[t[j]]+=(s[j]?1:-1);
      for(j=0;j<=1260;j++){
    stud[j+1]+=stud[j];
    re+=(stud[j]>0)&&(ts<=j)&&(j<te);
      }
      cout<<re<<endl;
    }
   }
  return 0;
}

C++: #include <iostream>
#include <vector>
#include <algorithm>

using namespace std;



int main(){

	int N,M,r;
	while(cin >> N >> M && !(N == 0 && M == 0)){
		// Ô
		vector<pair<int,int> > Gakusei[10001];
		cin >> r;
		pair<int,int> pc[1001];
		for(int i = 0; i < r; i++){
			int t;
			int n;
			int m;
			int s;
			cin >> t >> n >> m >> s;
			if(s == 1){
				pc[n].first = t;
			}
			else{
				pc[n].second = t;
				Gakusei[m].push_back(pc[n]);
			}
		}

		int q;
		cin >> q;
		for(int i = 0; i < q; i++){
			int cnt = 0;
			int ts,te,m;
			cin >> ts >> te >> m;
			sort(Gakusei[m].begin(),Gakusei[m].end());
			int cTime = ts;
			for(int j = 0; j < Gakusei[m].size(); j++){
				// æÃ~ÉJnÔª¢©ç©Ä¢­
				if(cTime >= Gakusei[m][j].second || Gakusei[m][j].first >= te)
					continue;
				else{
					cnt += (min(te,Gakusei[m][j].second) - max(cTime,Gakusei[m][j].first));
					cTime = Gakusei[m][j].second;
				}
			}
			cout << cnt << endl;
		}

	}
	return 0;
}