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 <stdio.h>
#include <stdlib.h>
#include <iostream>
#include <vector>
#include <string>
#include <queue>
#include <algorithm>
#include <math.h>
#include <utility>
#include <set>
#include <map>
#include <cstring>
#include <cstdio>
#include <stack>
#define INF 1000000000
#define rep(i,n) for(int i =0;i<n;i++)
using namespace std;
typedef long long int ll;


int main(){
    for(;;){
        int N,M;
        cin >> N>>M;
        if(!N and !M)break;
        int r;
        cin >> r;
        pair<int, int> g[1001][721];
        memset(g, 0, sizeof(g));
        for (int i=0; i<r; i++) {
            int t,n,m,s;
            cin >>t>>n>>m>>s;
            t-=540;
            if (s==1) {
                g[m][t] = {1,n};
            }else{
                g[m][t].first = 2;
                t--;
                while (t>=0 and g[m][t].second != n) {
                    g[m][t--].first=1;
                }
            }
        }
        int q;
        cin >>q;
        for (int qq = 0; qq < q; qq++) {
            int ts,te,m,ans = 0;
            cin >> ts >> te >>m;
            for (int i= ts-540; i<te-540; i++) {
                if (g[m][i].first ==1) {
                    ans++;
                }
            }
            cout << ans <<endl;
        }
    }
}

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

typedef struct{
  int time;
  bool inout;
} Data;

int main(){
  int n,m;
  while(cin>>n>>m,n){
    int r,q;
    Data data;
    vector<vector<Data> > vec(m);
    cin>>r;
    for(int i=0;i<r;i++){
      int t,pc,number,check;
      cin>>t>>pc>>number>>check;
      data.time=t;
      data.inout=(bool)check;
      vec[number-1].push_back(data);
    }
    cin>>q;
    for(int i=0;i<q;i++){
      int ts,te,number;
      cin>>ts>>te>>number;
      number--;
      int time=ts;
      int check=0;
      int sum=0;
      for(int i=0;i<(int)vec[number].size();i++){
	data = vec[number][i];
	if(data.inout) check++;
	else check--;
	if(ts <= data.time && data.time <= te){
	  if(data.inout && check == 1) time=data.time;
	  if(!data.inout&& check == 0){ 
	    sum += data.time-time;
	    time=data.time;
	  }
	}
	if(check!=1 && data.time > te){
	  sum+=te-time;
	  break;
	}
      }
      cout<<sum<<endl;
    }
  }
  return 0;
}

C++: #include <iostream>
#include <stdio.h>
#include <ctype.h>
#include <vector>
#include <string>
#include <algorithm>
using namespace std;


int main (){
  
  int pc,stu;
  
  while(1){

    cin >>pc>>stu;
    if (pc==0&&stu==0)break;
    
    int i,j,k,srec,sque,t,n,m,s,ts,te,sum;
    int record[pc][721]={};

    //record入力
    cin >>srec;
    for(i=0;i<srec;i++){
      cin >>t>>n>>m>>s;
      
      if (s==1){
	//ログイン
	for(j=t;j<721;j++){
	  record[n][j] = m;
	}
      }else{
	//ログアウト
	for(j=t+1;j<721;j++){
	  record[n][j] = 0;
	}
      }
    }
    
    //記録チェック
    sum = 0;
    cin >> sque;
    for(i=0;i<sque;i++){
      cin >> ts >>te >>m;
      for(j=ts;j<te+1;j++){
	for(k=0;k<pc;k++){
	  if (record[k][j]==m){
	    sum += 1;
	    break;
	  }
	}
      }
    }
    
    cout << sum <<endl;
    
  return 0;
}

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

struct Record{

  int s_cnt,e_cnt;
  int s[500],e[500];
  
};

int main(){

  int N,M;
  int r,q,t,n,m,s;
  int t_s,t_g;
  int table[721];
  
  while(1){
    
    cin >>N>>M;
    if(N==0 && M==0)break;
    
    Record student[M+1];
    
    for(int i=0 ; i < M+1 ; i++){
      student[i].s_cnt=0;
      student[i].e_cnt=0;
    }
    
    cin >>r;
    for(int i=0 ; i < r ; i++){
      cin >>t>>n>>m>>s;
      if(s == 1){
	student[m].s[student[m].s_cnt]=t;
	student[m].s_cnt++;
      }else{
	student[m].e[student[m].e_cnt]=t;
	student[m].e_cnt++;
      }
    }
    
    cin >>q;
    for(int i=0 ; i < q ; i++){
      cin >>t_s>>t_g>>m;
      for(int j=0 ; j < 721 ; j++)table[j]=0;
      for(int j=0 ; j < student[m].s_cnt ; j++){
	for(int k=student[m].s[j]-540 ; k < student[m].e[j]-540 ; k++){
	  table[k]=1;
	}
      }
      int sum=0;
      for(int j=t_s-540 ; j < t_g-540  ; j++)sum+=table[j];
      cout <<sum<<endl;
    }
    
  }
  
  return 0;
}