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>
#include <vector>

using namespace std;

struct log{
    int start;
    int end;
    int pc_number;
    int student_number;
    bool check;
};


int main() {
    while (1) {
        int N,M;
        vector<log> log_data;
        
        cin >> N >> M;
        if((N==0)||(M==0)) break;
        int r;
        cin >> r;
        while(r--){
            int t,n,m,s;
            cin >> t >> n >> m >> s;
            if(s==1){
                log temp = {t,0,n,m,false};
                log_data.push_back(temp);
            }
            else{
                vector<log>::iterator it=log_data.begin();
                while(1){
                    if(((it->pc_number==n)&&(it->student_number==m))&&(it->check==false)) {
                        it->end = t;
                        it->check = true;
                        break;
                    }
                    it++;
                }
            }
        }
        
        int q;
        cin >> q;
        while(q--){
            int t_s,t_e,m,total=0;
            cin >> t_s >> t_e >> m;
            
            vector<log>::iterator it;
            int i=t_s;
            while(i < t_e){
                it = log_data.begin();
                while(it != log_data.end()){
                    if(it->student_number == m){
                        if((it->start <= i)&&(i < it->end)){
                            total++;
                            break;
                        }
                    }
                    it++;
                }
            i++;
            }
            cout << total <<endl;
        }
    
    }
    
}

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

int table[10001][1261];

int main(){
  int N, M, r, q, t, s, n, m,ts,te;

  while(cin >> N >> M, N && M){
    cin >> r;
    for(int i = 0; i < r; i++){
      cin >> t >> n >> m >> s;
      if(s) table[m][t]++;
      else  table[m][t]--;
    }
    for(int i = 1; i <= M; i++){
      for(int j = 540; j <= 1260; j++){
	table[i][j] += table[i][j-1];
      }
    }
 
    for(int i = 1; i <= M; i++){
      for(int j = 540; j <= 1260; j++){
	//if(i == 1)cout << table[i][j] << endl;
	if(table[i][j] > 1) table[i][j] = 1;
	table[i][j] += table[i][j-1];
      }
    }
    cin >> q;
    for(int i = 0; i < q; i++){
      cin >> ts >> te >> m;
      cout << table[m][te-1] - table[m][ts-1] << endl;
    }
    /*for(int i = 540; i < 1260; i++) {cout << i << " " << table[1][i];
    if(i == te || i == ts) cout << "ttt";
    cout << endl;}
    */
  }
}

C++: #include <iostream>
#include <stack>
#include <queue>

using namespace std;

int main()
{
    int N,M;
    while(cin>>N>>M){
        if(N==0&&M==0)break;
        int r;
        cin>>r;
        int data[1000][4];
        for(int i=0; i<r; i++){
            int tt,nn,mm,ss;
            cin>>tt>>nn>>mm>>ss;
            data[i][0]=tt;
            data[i][1]=nn;
            data[i][2]=mm;
            data[i][3]=ss;
            
        }
        
        int q;
        cin>>q;
        for(int roop=0; roop<q; roop++){
            int ts,te,mm;
            cin>>ts>>te>>mm;
            int start=ts;
            int ret=0;
            
            queue<int> qu;
            for(int i=0; i<r; i++){
                if(data[i][2]==mm){//dataが対象人物
                    if(data[i][3]==1){//ログインなら
                        if(qu.empty()){
                            start=data[i][0];
                            if(start<ts)start=ts;

                        }
                        qu.push(data[i][1]);
                    }else{//ログアウトなら
                        int qusize=qu.size();
                        for(int j=0; j<qusize; j++){
                            int pc = qu.front();
                            qu.pop();
                            if(pc==data[i][1])break;
                            else qu.push(pc);
                        }
                        int end = data[i][0];
                        if(qu.empty()){
                            if(end>te)end=te;
                            ret+=end-start;
                        }
                    }

                }
            }
            
            if(!qu.empty()){
                if(start<te)ret+=te-start;
            }
            cout<<ret<<endl;
            
        }
    }
    
    return 0;
}

C++: #include<bits/stdc++.h>
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;
}