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 <algorithm>
#include <vector>
#include <tuple>

int main()
{
	while(true){
		int N, M;

		std::cin >> N >> M;
		if ( N == 0 && M == 0 ) break;

		int r;
		std::cin >> r;

		std::vector<std::tuple<int, int, int>> data(r);
		for ( int i = 0; i < r; ++i ) {
			auto &v = data[i];

			int n;
			std::cin >> std::get<0>(data[i]);
			std::cin >> n;
			std::cin >> std::get<1>(data[i]);
			std::cin >> std::get<2>(data[i]);
		}

		std::sort(data.begin(), data.end());
		int q;
		std::cin >> q;
		for ( int i = 0; i < q; ++i ) {
			int s, e, m;
			std::cin >> s >> e >> m;

			int be = s;
			int sum = 0;
			int pc = 0;
			for ( int j = 0; j < r; ++j ) {
				if ( std::get<1>(data[j]) == m ) {
					if ( std::get<2>(data[j]) == 1 ) {
						pc++;
					}else {
						pc--;
					}

					if ( std::get<2>(data[j]) == 1 && std::get<0>(data[j]) >= e && pc == 1 ) break;
					if ( be < std::get<0>(data[j]) && std::get<2>(data[j]) == 1 ) {
						if ( pc == 1 )
							be = std::get<0>(data[j]);
					}
					if ( std::get<2>(data[j]) == 0 ) {
						if ( e > std::get<0>(data[j]) ) {
							if ( pc == 0 )
								sum += std::get<0>(data[j]) - be;
						} else {
							sum += e - be;
							break;
						}
					}
				}
			}
			std::cout << sum << std::endl;
		}
	}
	
	return 0;
}

C++: #include<iostream>
#include<sstream>
#include<algorithm>
#include<numeric>
#include<vector>
#include<map>
#include<set>
#include<queue>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cassert>

#define rep(i,n) for(int i=0;i<n;i++)
#define all(c) (c).begin(),(c).end()
#define fr(i,c) for(__typeof((c).begin()) i=(c).begin();i!=(c).end();i++)
#define mp make_pair
#define pb push_back
#define dbg(x) cerr<<#x<<" = "<<(x)<<endl

using namespace std;

typedef long long ll;
typedef vector<int> vi;
typedef pair<int,int> pi;

const int inf=1<<28;
const double INF=1e12,EPS=1e-9;

int main()
{
  int n,m,r,q;
  while(cin>>n>>m,n){
    cin>>r;
    //cerr<<r<<endl;
    map<int,int> use[m+1];
    rep(i,r){
      int t,n1,m1,s; cin>>t>>n1>>m1>>s;
      use[m1][t]+=s?1:-1;
    }
    cin>>q;
    //cerr<<q<<endl;

    rep(i,q){
      int ts,te,m; cin>>ts>>te>>m;
      int prev=use[m].begin()->first,in=0,ans=0;
      fr(j,use[m]){
	if(in>0)ans+=max(0,min(j->first,te)-max(prev,ts));
	prev=j->first;
	in+=j->second;
      }
      cout<<ans<<endl;
    }
  }
  return 0;
}

C++: #include<iostream>

using namespace std;

#define MMAX 100
#define tMAX (60*24)
int main(){

	int N, M;
	int r;
	int t, n, m1, s;
	int q;
	int ts, te, m2;
	int num,cnt;
	int data[MMAX+1][tMAX+1];

	while (1){
		cin >> N >> M;
		if (N == 0 && M == 0) break;
		for (int i = 0; i <= MMAX; i++){
			for (int j = 0; j <= tMAX; j++){
				data[i][j] = 0;
			}
		}
		cin >> r;
		for (int i = 0; i < r; i++){
			cin >> t >> n >> m1 >> s;
			if (s == 0) data[m1][t]=-1;
			else data[m1][t]=1;
		}
		cin >> q;
		for (int i = 1; i <= M; i++){
			num = 0;
			for (int j = 0; j <= tMAX; j++){
				num += data[i][j];
				data[i][j] = num;
			}
		}
		for (int i = 0; i < q; i++){
			cin >> ts >> te >> m2;
			cnt = 0;
			for (int j = ts; j < te; j++){
				if (data[m2][j] >= 1) cnt++;
			}
			cout << cnt << endl;
		}
	}
	return 0;
}