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;

typedef vector<int> V;

typedef struct{
  int t,n,m,s;
} Record;

int main(){
  int n,m,r,q;
  
  while(cin >> n >> m ,n + m){
    const int MAX = 1260-540;

    cin >> r;
    Record d[r];
    vector<V> v(m,V(MAX+1,2)),cnt(m,V(MAX+1,0));

    for(int i = 0 ; i < r ; i++){
      cin >> d[i].t >> d[i].n >> d[i].m >> d[i].s;
      v[--d[i].m][d[i].t-540] = d[i].s;
    }

    for(int i = 0 ; i < m ; i++){
      cnt[i][0] = (v[i][0] == 1) ? 1 : 0;
      for(int j = 1 ; j < MAX ; j++){
	cnt[i][j] = cnt[i][j-1] + ((v[i][j] == 1) ? 1 : 0);
	if(v[i][j] == 0) cnt[i][j]--;
      }
    }

    int ts,tt,sn;
    cin >> q;
    for(int i = 0 ; i < q ; i++){
      cin >> ts >> tt >> sn;

      sn--;
      int ans = 0;
      for(int i = ts ; i < tt ; i++){
	if(cnt[sn][i-540] != 0) ans++;
      } 
      cout << ans << endl;
    }
  }

  return 0;
}

C++: #include <iostream>
#include <vector>
#include <string>
#include <stack>
#include <queue>
#include <deque>
#include <set>
#include <map>
#include <algorithm>	// require sort next_permutation count __gcd reverse etc.
#include <cstdlib>	// require abs exit atof atoi 
#include <cstdio>		// require scanf printf
#include <functional>
#include <numeric>	// require accumulate
#include <cmath>		// require fabs
#include <climits>
#include <limits>
#include <cfloat>
#include <iomanip>	// require setw
#include <sstream>	// require stringstream 
#include <cstring>	// require memset
#include <cctype>		// require tolower, toupper
#include <fstream>	// require freopen

#define rep(i,n) for(int i=0;i<(n);i++)
#define ALL(A) A.begin(), A.end()

using namespace std;

typedef long long ll;
typedef pair<int, int> P;
bool tt[1300];

int main()
{
//	cut here before submit 
//	freopen ("testcase.ALLR", "r", stdin );
	int N, M;
	while (scanf ("%d %d", &N, &M ), N, M ){
		vector<int> login[M][N], logout[M][N];
		rep (i, M ){
			rep (j, N ){
				login[i][j].clear();
				logout[i][j].clear();
			} // end rep
		} // end rep

		int r;
		scanf ("%d", &r );
		rep (i, r ){
			int t, n, m, s;
			scanf ("%d %d %d %d", &t, &n, &m, &s );
			n--;m--;
			if (s == 1 ){
				login[m][n].push_back (t );
			}else{
				logout[m][n].push_back (t );
			} // end if
		} // end rep
		int q;
		scanf ("%d", &q );
		vector<int> ans (q, 0 );
		rep (i, q ){
			int ts, te, m;
			scanf ("%d %d %d", &ts, &te, &m );
			m--;
			memset (tt, false, sizeof (tt ) );
			rep (j, N ){
				if (!login[m][j].empty() ){
					rep (k, login[m][j].size() ){
						for (int l = login[m][j][k]; l < logout[m][j][k]; l++ ){
							tt[l] = true;
						} // end for
					} // end rep
				} // end if
			} // end rep
			int res = 0;
			for (int t = ts; t < te; t++ ){
				if (tt[t] ) res++;
			} // end if
			ans[i] = res;
		} // end rep
		rep (i, q ){
			printf ("%d\n", ans[i] );
		} // end rep
			
	} // end loop
		
	return 0;
}

C++: #include <bits/stdc++.h>
#define For(i, a, b) for(int (i)=(int)(a); (i)<(int)(b); ++(i))
#define rFor(i, a, b) for(int (i)=(int)(a)-1; (i)>=(int)(b); --(i))
#define rep(i, n) For((i), 0, (n))
#define rrep(i, n) rFor((i), (n), 0)
#define fi first
#define se second
using namespace std;
typedef long long lint;
typedef unsigned long long ulint;
typedef pair<int, int> pii;
typedef pair<int, lint> pil;
typedef pair<lint, lint> pll;
template<class T> bool chmax(T &a, const T &b){if(a<b){a=b; return true;} return false;}
template<class T> bool chmin(T &a, const T &b){if(a>b){a=b; return true;} return false;}
template<class T> T div_floor(const T a, const T b){return a>=0 ? a/b : (a+1)/b-1;}
template<class T> T div_ceil(const T a, const T b){return a>=0 ? (a-1)/b+1 : a/b;}

constexpr lint mod = 1e9+7;
constexpr lint INF = mod*mod;
constexpr int MAX = 100010;

int N, M, r, q;
int cnt[10010][1300];

int main(){
    while(scanf("%d%d", &N, &M) && N){
        rep(i, M)rep(j, 1300) cnt[i][j] = 0;
        scanf("%d", &r);
        rep(_, r){
            int t, n, m, s;
            scanf("%d%d%d%d", &t, &n, &m, &s);
            --m;
            if(s == 1) ++cnt[m][t];
            else --cnt[m][t];
        }
        rep(i, M)rep(j, 1299) cnt[i][j+1] += cnt[i][j];
        scanf("%d", &q);
        rep(_, q){
            int s, t, m;
            scanf("%d%d%d", &s, &t, &m);
            --m;
            int ans = 0;
            For(i, s, t) ans += (cnt[m][i] > 0);
            printf("%d\n", ans);
        }
    }
}