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<cstring>
using namespace std;
struct student{
  int start[1000];
  bool used[721];
};
student S[10000];
int main(){
  int N,M;
  while(cin>>N>>M){
    if(N==0)break;
    int r,q;
    memset(S,0,sizeof(S));  
    cin>>r;
    for(int i=0;i<r;i++){
      int t,n,m,s;
      cin>>t>>n>>m>>s;
      t-=540;m--;
      if(s==1){
	S[m].start[n]=t;
      }else{
	while(t>0 && S[m].start[n]<t)
	  S[m].used[--t]=true;
      }
    }
    cin>>q;
    for(int i=0;i<q;i++){
      int ts,te,m,ans=0;
      cin>>ts>>te>>m;
      ts-=540;te-=540;m--;
      for(int i=ts;i<te;i++){
	if(S[m].used[i]==true)ans++;
      }
      cout << ans << endl;
    }
  }
  return 0;
}

C++: 
//http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=1148&lang=jp

#include<iostream>
#include<map>
#include<vector>
#include<algorithm>
#include<cmath>
#include<climits>
#include<ctime>
#include<cstring>
#include<numeric>

#define ALL(v) (v).begin(),(v).end()
#define REP(i,p,n) for(int i=p;i<(int)(n);++i)
#define rep(i,n) REP(i,0,n)
#define dump(a) (cerr << #a << "=" << (a) << endl)
#define DUMP(list) cout << "{ "; for(auto nth : list){ cout << nth << " "; } cout << "}" << endl;

using namespace std;

int main()
{
	int N,M;

	while(cin >> N >> M && N)
	{
		vector<int> PC(N+1);
		int record[M+1][1261];
		fill_n((int *)record, sizeof(record) / sizeof(int), 0);

		int R;
		cin >> R;
		rep(i,R)
		{
			int t,n,m,s;
			cin >> t >> n >> m >> s;
			if(s == 1){
				PC[n] = t;
			}else{
				REP(i,PC[n],t){
					record[m][i] = 1;
				}
				PC[n] = 0;
			}
		}

		int Q;
		cin >> Q;
		rep(i,Q)
		{
			int ts, te, m;
			cin >> ts >> te >> m;
			int time=0;
			REP(i,ts,te){
				if(record[m][i]){ time+=1; }
			}
			cout << time << endl;
		}
	}

	return 0;
}

C++: #include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <cmath>
#include <cstdio>
#include <functional>
#include <numeric>
#include <stack>
#include <queue>
#include <map>
#include <set>
#include <utility>
#include <sstream>
#include <complex>
#include <fstream>

using namespace std;

#define FOR(i,a,b) for(long long i=(a);i<(b);i++)
#define REP(i,N) for(long long i=0;i<(N);i++)
#define ALL(s) (s).begin(),(s).end()
#define fi first
#define se second

#define PI acos(-1.0)
#define INF 10e15+9
#define MOD 1000000007
#define EPS 1e-10
#define MAX_N 100100
#define MAX_M 100100

typedef long long ll;
typedef pair<ll, ll> P;
typedef pair<double, double> PD;
typedef pair<string, ll> PS;
typedef vector<ll> V;
typedef pair<P, char> PC;

int N, M, r, q;

int t, n, m, s, ts, te;

int time[1010][10010];
bool used[1000][10010];

int main(){
	while (cin >> N >> M&&N + M){
		cin >> r;
		REP(i, r){
			cin >> t >> n >> m >> s;
			t -= 540;
			if (s == 1){
				time[n][m] = t;
			}
			else{
				FOR(j, time[n][m], t){
					used[j][m] = 1;
				}
			}
		}
		cin >> q;
		REP(i, q){
			int ans = 0, t = -1;
			cin >> ts >> te >> m;
			ts -= 540;
			te -= 540;
			FOR(j, ts, te + 1){
				if (t == -1){
					if (used[j][m])t = j;
				}
				else{
					if (!used[j][m]){
						//cout << "!" << endl;
						//cout << j - 1 << " " << t << endl;
						ans += j - t;
						t = -1;
					}
				}
			}
			if (t != -1){
				ans += te - t;
			}
			cout << ans << endl;
		}
	}
}

C++: #include<iostream>
#include<vector>

using namespace std;

struct DATA{
  int info1;
  int info2;
};

vector<DATA> Convert(vector<DATA>);
int getTime(vector<DATA>, int, int);

int main(){
  int i, n, m, r, q, time, log, t1, t2, ans;
  DATA _data;

  while(1){
    cin >> n >> m;
    if(n == 0 && m == 0) break;

    vector< vector<DATA> > data1(m), data2;
    cin >> r;

    for(i=0; i<r; ++i){
      cin >> time >> n >> m >> log;
      _data.info1 = time;
      _data.info2 = log;
      data1[m-1].push_back(_data);
    }

    for(i=0; i<data1.size(); ++i)
      data2.push_back(Convert(data1[i]));

    cin >> q;

    for(i=0; i<q; ++i){
      cin >> t1 >> t2 >> m;
      cout << getTime(data2[m-1], t1, t2) << endl;
    }
  }
  return 0;
}

vector<DATA> Convert(vector<DATA> data1){
  int i, j, in_count, out_count;
  DATA _data;
  vector<DATA> data2;

  i = 0;
  j = i;
  in_count = 0;
  out_count = 0;
  while(j < data1.size()){
    if(data1[j].info2 == 1) ++in_count;
    else ++out_count;

    if(in_count == out_count){
      _data.info1 = data1[i].info1;
      _data.info2 = data1[j].info1;
      data2.push_back(_data);
      i = j + 1;
      in_count = 0;
      out_count = 0;
    }
    ++j;
  }

  return data2;
}

int getTime(vector<DATA> data, int start, int end){
  int i, ans;

  for(i=0, ans=0; i<data.size(); ++i){
    if(start < data[i].info1 && data[i].info1 < end && end < data[i].info2)
      ans += (end - data[i].info1);
    else if(data[i].info1 < start && start < data[i].info2 && data[i].info2 < end)
      ans += (data[i].info2 - start);
    else if(data[i].info1 < start && end < data[i].info2)
      ans += (end - start);
    else if(start <= data[i].info1 && data[i].info2 <= end)
      ans += (data[i].info2 - data[i].info1);
  }
  return ans;
}