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>
#include <utility>


using namespace std;

int main(void)
{
  while (true) {
    int n, m;
    cin >> n >> m;
    if (n == 0 && m == 0) break;
    int r;
    cin >> r;
    int time[r], pc[r], stu[r], log[r];
    

    for (size_t i = 0; i < r; i++) {
      cin >> time[i] >> pc[i] >> stu[i] >> log[i];   
    }
    int que;
    cin >> que;
    int ts[que], te[que], qm[que];
    for (size_t i = 0; i < que; i++) {
      cin >> ts[i] >> te[i] >> qm[i];
    }
    //??\??????

    for (size_t k = 0; k < que; k++) {

      int start = ts[k];
      int end = te[k];
      int diff = end - start;
      int student = qm[k];
      vector<int> timecount;
      timecount.resize(diff);
      for (size_t i = 0; i < diff; i++)
	timecount[i] = 0;

      for (size_t i = 0; i < r; i++) {
	int intime, outtime;

	//question????????????recode ??????????????°????????????
	if (student == stu[i] && log[i]) {
	  intime = time[i];
	  //pc????????§???
	  int pcnum = pc[i]; 
	  int j = i + 1;
	  //?????°??¢???????¨?????????¢???
	  while (true) {
	    if(student == stu[j] && pcnum == pc[j]) {
	      outtime = time[j];

	      if (intime < start) intime = start;
	      if (outtime > end) outtime = end;
	      intime -= start;
	      outtime -= start;

	         
	      for (int l = intime; l < outtime; l++)
		timecount[l] = 1;
	      break;
	    }
	    j++;
	    if (j > r)
	      break;
	  }
	}
      }
      int cnt = 0;
      for (size_t i = 0; i < diff; i++){
	if (timecount[i])
	  cnt++;
      }
      cout << cnt << endl;
     

    }
  }
  
  
  return true;
  
}

C++: #include<bits/stdc++.h>
using namespace std;
#define inf 1e9
#define ll long long
#define ull unsigned long long
#define M 1000000007
#define P pair<int,int>
#define PLL pair<ll,ll>
#define FOR(i,m,n) for(int i=m;i<n;i++)
#define RFOR(i,m,n) for(int i=m;i>=n;i--)
#define rep(i,n) FOR(i,0,n)
#define rrep(i,n) RFOR(i,n,0)
#define all(a) a.begin(),a.end()
const int vx[4] = {0,1,0,-1};
const int vy[4] = {1,0,-1,0};
#define PI 3.14159265

int e[11000][1300];

void f(int n,int m){
  rep(i,11000){
    rep(j,1300){
      e[i][j]=0;
    }
  }
  int r;
  cin>>r;
  while(r-- >0){
    int a,b,c,d;
    cin>>a>>b>>c>>d;
    if(d==1){
      e[c][a+1]++;
    }
    else{
      e[c][a+1]--;
    }
  }
  rep(i,11000){
    FOR(j,1,1300){
      e[i][j]+=e[i][j-1];
    }
    FOR(j,1,1300){
      e[i][j]= (e[i][j]>0);
      e[i][j]+=e[i][j-1];
    }
  }

  int q;
  cin>>q;
  while(q-- >0){
    int a,b,c;
    cin>>a>>b>>c;
    int ans = e[c][b]-e[c][a];
    cout<<ans<<endl;
  }

}


int main(){
  while(1){
    int n,m;
    cin>>n>>m;
    if(n==0) break;
    f(n,m);
  }

  return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;

typedef long long int ll;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<pair<int, int> > vii;
#define rrep(i, m, n) for(int (i)=(m); (i)<(n);  (i)++)
#define erep(i, m, n) for(int (i)=(m); (i)<=(n); (i)++)
#define  rep(i, n)    for(int (i)=0; (i)<(n);  (i)++)
#define rrev(i, m, n) for(int (i)=(n)-1; (i)>=(m); (i)--)
#define erev(i, m, n) for(int (i)=(n); (i)>=(m); (i)--)
#define  rev(i, n)    for(int (i)=(n)-1; (i)>=0; (i)--)
#define vrep(i, c)    for(__typeof((c).begin())i=(c).begin(); i!=(c).end(); i++)
#define  ALL(v)       (v).begin(), (v).end()
#define pb            push_back
template<class T, class S> inline pair<T, S> mp(T x, S y){ return make_pair(x, y); }
template<class T, class S> inline bool minup(T& m, S x){ return m>(T)x ? (m=(T)x, true) : false; }
template<class T, class S> inline bool maxup(T& m, S x){ return m<(T)x ? (m=(T)x, true) : false; }

static const int    INF = 1000000000;
static const ll     MOD = 1000000007LL;
static const double EPS = 1E-12;

const int MAX_M = 11111;
const int MAX_R = 1111;
const int MAX_Q = 55;
const int MAX_T = 800;
int id[MAX_M][MAX_T];
int N, M;
int r, q;
struct _R{int t, m, n, s;} R[MAX_R];
int ts, te, m;

int main()
{
  while(cin >> N >> M, N){
    rep(i, M) rep(j, 777) id[i][j] = 0;
    cin >> r;
    rep(i, r) cin >> R[i].t >> R[i].n >> R[i].m >> R[i].s;
    rep(i, r) if(!R[i].s) R[i].s = -1;

    rep(i, r) id[R[i].m - 1][R[i].t - 540] = R[i].s;
    rep(i, M) rep(j, 777) id[i][j] += id[i][j - 1];

    cin >> q;
    rep(i, q){
      cin >> ts >> te >> m;
      int res = 0;
      rrep(j, ts, te) if(id[m - 1][j - 540]) res += 1;
      cout << res << endl;
    }
  }

  return 0;
}