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>
using namespace std;

int main(){
	int n,m,r,q;
	int cnt[1000][1261];
	while(cin >> n >> m,n){
		for(int i = 0;i < m;i++){
			for(int j = 0;j <= 1260;j++) cnt[i][j] = 0;
		}
		cin >> r;
		for(int i = 0;i < r;i++){
			int t,a,b,s;
			cin >> t >> a >> b >> s; b--;
			if(s) cnt[b][t]++;
			else cnt[b][t]--;
		}
		for(int i = 0;i < m;i++){
			for(int j = 1;j <= 1260;j++){
				cnt[i][j] += cnt[i][j - 1];
				//if(j >= 774 && j <= 881) cout << cnt[i][j] << " ";
			}
			//cout << endl;
		}
		for(int i = 0;i < m;i++){
			for(int j = 1;j <= 1260;j++){
				if(cnt[i][j]) cnt[i][j] = 1;
			}
		}
		for(int i = 0;i < m;i++){
			for(int j = 1;j <= 1260;j++){
				cnt[i][j] += cnt[i][j - 1];
			}
		}
		cin >> q;
		for(int i = 0;i < q;i++){
			int s,t,b;
			cin >> s >> t >> b; b--;
			cout << cnt[b][t - 1] - cnt[b][s - 1] << endl;
		}
	}
	return 0;
}

C++: #include<iostream>
#include<string>
#include<vector>
#include<utility>
#include<queue>
#include<algorithm>
#include<cmath>
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<map>
#include<complex>
#define INF 2147483647
#define llINF 9223372036854775807
#define pb push_back
#define mp make_pair 
#define F first
#define S second
#define ll long long

using namespace std;
int main(){
  int n,m;
  while(cin>>n>>m,n){
    short ans[m][1261]={};
    int r;cin>>r;
    for(int i=0;i<r;i++){
      int t,nn,mm,s;cin>>t>>nn>>mm>>s;
      mm--;
      if(s==1)
	ans[mm][t]=1;
      else{
	ans[mm][t]=-1;
      }
    }
    int q;cin>>q;
    for(int i=0;i<q;i++){
      int t,tt,mm;cin>>t>>tt>>mm;mm--;
      int ans2=0;
	int cnt=0;
      for(int j=0;j<=2000;j++){

	cnt+=ans[mm][j];
	//cout<<cnt<<endl;;
	if(cnt>0&&j<tt&&t<=j){ans2++;}
      }
      cout<<ans2<<endl;
    }
  }
  return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
#define rep(i,n) repi(i,0,n)
#define repi(i,a,b) for(int i=(int)(a);i<(int)(b);i++)
#define MOD 1000000007
#define ADD(X,Y) ((X) = ((X) + (Y)%MOD) % MOD)
typedef long long i64; typedef vector<int> ivec; typedef vector<string> svec; typedef pair<int, int> pi;
int dd[] = { 0, 1, 0, -1, 0 };
#define all(u) begin(u),end(u)
#define mp make_pair
#define pb push_back


int main()
{
  while(true)
    {
      int N, M;
      scanf("%d%d", &N,&M);
      if(N == 0 && M == 0)break;
      int A[M+1][1500]={0};
      int r;
      scanf("%d", &r);
      rep(i, r)
	{
	  int t, n, m, s;
	  scanf("%d%d%d%d", &t, &n, &m, &s);
	  if(s == 1)
	    {
	      A[m][t]++;
	    }
	  else
	    {
	      A[m][t+1]--;
	    }
	}
      repi(i, 1, M + 1)
	{
	  rep(t, 1300)
	    {
	      if(t == 0)continue;
	      A[i][t] += A[i][t-1];
	    }
	}

      int q;
      scanf("%d", &q);
      rep(i, q)
	{
	  int ts, te, m;
	  scanf("%d%d%d", &ts,&te,&m);
	  int start = -1;
	  int ans = 0;
	  repi(t, ts, te+1)
	    {
	      if(start == -1)
		{
		  if(A[m][t] > 0)
		    {
		      start = t;
		    }
		}
	      else
		{
		  if(A[m][t] <= 0)
		    {
		      ans += t - start - 1;
		      start = -1;
		    }
		}
	    }
	  if(start != -1)ans += te - start;
	  printf("%d\n", ans);
	}
    }
  return 0;
}