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 <bits/stdc++.h>
using namespace std;

int main() {
    int N, M;
    while (cin >> N >> M, N | M) {
        int r, q;
        cin >> r;
        vector<vector<int> > v(10001, vector<int>(1265, 0));
        for (int i = 0; i < r; i++) {
            int t, n, m, s;
            cin >> t >> n >> m >> s;
            for (int j = 0; j < 1260; j++) {
                if (j >= t) {
                    if (s) {
                        v[m][j]++;
                    } else {
                        v[m][j]--;
                    }
                }
            }
        }
        cin >> q;
        for (int i = 0; i < q; i++) {
            int ts, te, m, ans = 0;
            cin >> ts >> te >> m;
            for (int j = ts; j < te; j++) {
                if (v[m][j]) ans++;
            }
            cout << ans << endl;
        }
    }
    return 0;
}

C++: #include <iostream>
#define R 1000
#define TMAX 1261
using namespace std;
int main(){
  int N,M,r,q,t[R],n[R],m[R],s[R],end[R],ts,te,m1,cnt,lim,time[TMAX];
  while(1){
    cin >> N >> M;
    if(N==0&&M==0) break;
    cin >> r;
    for(int i=0;i<r;i++){
      cin >> t[i] >> n[i] >> m[i] >> s[i];
    }
    cin >> q;
    for(int i=0;i<q;i++){
      cin >> ts >> te >> m1;
      for(int j=ts;j<=te;j++){
    time[j]=0;
      }
      for(int j=0;j<r;j++) end[j]=0;
      cnt=0;
      for(int j=0;j<r;j++){
    if(end[j]==0){
      end[j]=1;
      if(m1==m[j]){
        for(int k=j+1;k<r;k++){
          if(m1==m[k]&&n[j]==n[k]&&end[k]==0){
        end[k]=1;
        for(int l=t[j]+1;l<=t[k];l++){
          if(time[l]==0&&ts<l&&l<=te){
            time[l]=1;
            cnt++;
          }
        }
        break;
          }
        }
      }
    }
      }
      cout << cnt << endl;
    }
  }
  return 0;
}

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


int students[10001][800] = {};
int numlogin[10001] = {};
int sum[10001][800]={};
int main(){

  while(1){
    int N,M,r;
    cin >> N >> M;
    if(!N and !M) break;

    cin >> r;
    // 4byte * 10^7

    memset(students,0,sizeof(students));
    memset(numlogin,0,sizeof(numlogin));
    memset(sum,0,sizeof(sum));

    // ?¨????
    for(int i=0; i<r; i++){ // 1000
      int t,n,m,s;
      cin >> t >> n >> m >> s;
      t -= 560;
      if(s == 0) { // ?????°??¢??????
	numlogin[m]--;
	if(numlogin[m] == 0){
	  for(int i=t-1; students[m][i] != 1 and t>=0; i--){ // 1000
	    students[m][i] = 1;
	  }
	}
      }
      else{ // ?????°??????
	numlogin[m]++;
	if(numlogin[m] == 1)
	  students[m][t] = 1;
      }
    }

    // ?´???????

    for(int i=1; i<=M; i++){ // 100000
      for(int j=1; j<790; j++){ // 1000
	sum[i][j] = sum[i][j-1] + students[i][j]; 
	//	students[i][j] += students[i][j-1];
      }
    }

    // ??????
    int  q;
    cin >> q;
    for(int i=0; i<q; i++){
      int ts,te,id;
      cin >> ts >> te >> id;
      ts -= 560;
      te -= 560;
      cout << sum[id][te-1] - sum[id][ts] + students[id][ts] << endl;
      //      cout << students[id][te] - students[id][ts] << endl;
      //cout << students[id][te] - students[id][ts] << endl;
    }
  }
}

C++: #include <iostream>
#include <algorithm>
using namespace std;
enum{LOGOUT,LOGIN};
const int MAX_T=1260+1-540;
int tomin(int d){
     return d-540;
}
bool table[10000+1][MAX_T];
int login[1000+1];

int main(){
     int N,M;
     while(cin>>N>>M,N||M){
	  int r;
	  cin>>r;
	  for(int i=0;i<M+1;i++){
	       for(int j=0;j<MAX_T;j++){
		    table[i][j]=false;
	       }
	  }
	  for(int i=0;i<r;i++){
	       int t,n,m,s;
	       cin>>t>>n>>m>>s;
	       t=tomin(t);
	       switch(s){
	       case LOGIN:
		    login[n]=t;
		    break;
	       case LOGOUT:
		    fill(&table[m][login[n]],&table[m][t],true);
		    break;
	       }
	  }
	  int q;
	  cin>>q;
	  for(int i=0;i<q;i++){
	       int ts,te,m;
	       cin>>ts>>te>>m;
	       ts=tomin(ts);te=tomin(te);
	       cout<<count(&table[m][ts],&table[m][te],true)<<endl;
	  }
     }
}

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

using namespace std;
typedef pair<int, int> pii;

int main(){

    while(1){
        int N, M;
        cin>> N>> M;
        if(!(N||M)) break;
        int r;
        cin>> r;

        int a[M][1270];
        for(int i=0; i<M; i++){
            for(int j=0; j<1270; j++){
                a[i][j]=0;
            }
        }
        for(int i=0; i<r; i++){
            int t, n, m, s;
            cin>> t>> n>> m>> s;
            n--; m--;
            if(s){
                a[m][t]+=1;
            }else{
                a[m][t]-=1;
            }
        }
        for(int i=0; i<M; i++){
            for(int j=1; j<1270; j++){
                a[i][j]+=a[i][j-1];
            }
        }

        int Q;
        cin>> Q;
        for(int i=0; i<Q; i++){
            int s, e, m;
            cin>> s>> e>> m;
            m--;
            int k=0;
            for(int j=s; j<e; j++){
                k+=(a[m][j]>0);
            }
            cout<< k<< endl;
        }
    }

    return 0;
}