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 <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][0]>=te)break;
                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=(int)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 <stdio.h>
#include <algorithm>
#include <iostream>
#include <stack>
#include <vector>
#include <math.h>

using namespace std;

struct PC{
	int login_time;
};


bool** timeTable;

void func(int numPC,int numStudent){

	for(int i = 0; i < 10001; i++){
		for(int k = 0; k < 721;k++){
			timeTable[i][k] = false;
		}
	}

	PC pcInfo[1001];

	int r,time,pc_id,student_id,type;

	scanf("%d",&r);

	for(int i = 0; i < r; i++){
		scanf("%d %d %d %d",&time,&pc_id,&student_id,&type);

		if(type == 1){ //?????°???????¨????
			pcInfo[pc_id].login_time = time;
		}else{ //?????°??¢???????¨????<bool??¨????????????>
			for(int k = pcInfo[pc_id].login_time; k <= time; k++){
				timeTable[student_id][k-540] = true;
			}
			pcInfo[pc_id].login_time = 0;
		}
	}

	int q,start,end,count,left,right;

	scanf("%d",&q);

	for(int i = 0; i < q; i++){
		scanf("%d %d %d",&start,&end,&student_id);

		count = 0;
		left = -1,right = -1;

		for(int k = start; k <=end; k++){
			if(timeTable[student_id][k-540]){
				if(left == -1){
					left = k-540;
				}else{
					right = k - 540; //?¬????false?????????????????\??????????????§?????????right??´??°
				}
				if(k == end){
					if(right == -1){ //????????????????????°??????????????´???
						//Do nothing
					}else{
						count += right - left;
					}
				}
			}else{
				if(right != -1){
					count += right - left;
					left = right = -1;
				}
			}
		}
		printf("%d\n",count);
	}
}


int main(){

	int numPC,numStudent;

	timeTable = new bool*[10001];
	for(int i = 0; i < 10001; i++){
		timeTable[i] = new bool[721];
	}

	while(true){
		scanf("%d %d",&numPC,&numStudent);
		if(numPC == 0 && numStudent == 0)break;

		func(numPC,numStudent);
	}

    return 0;
}

C++: #include<iostream>
#include<vector>
using namespace std;
struct log{
  int t,n,m,s;
  bool operator<(const log&a)const{
    return n==a.n ? (m == a.m? t < a.t : m < a.m) : n<a.n;
  }
};
int main(){
  int nu,me,i,j,k,o,f;
  cin >> nu >> me;
  while(nu!=0||me!=0){
    int r,q;
    cin >> r;
    int t,n,m,s,ts,te;
    vector <log> logs;
    log l;
    for(i=0;i<r;i++){
      cin >> l.t >> l.n >> l.m >> l.s ;
      logs.push_back(l);
    }
    cin >> q;
    sort(logs.begin(),logs.end());
    i=0;

    int a;
    for(a=0;a<q;a++){
      cin >> ts >> te >> m ;
      
      j=0;
      o=0;
      f=0;
      for(i=ts;i<te;i++){
	f=0;
	k=0;
	for(j=0;j<logs.size();j+=2){
	  if(logs[j].m==m&&logs[j].t<=i&&i<logs[j+1].t){
	    f=1;
	  }
	}
	
	o+=f;
      }
      cout << o << endl;
    }
    
    cin >> nu >> me;
  }
  return 0;
}